I've never been one to like house rules (unless they are mine -

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A BATTLETECH* guide to making your 'Mechs unique
©1991 by Mike Speca
* Reposted without permission *
Copied from Dragon Magazine (free PDF) Issue 166 pp 16 & 17
http://dnd.ezael.net/~olep/Drmg166.pdf
While reading Technical Readout 3025 and Technical Readout 3026,
put out by the FASA Corporation for the BATTLETECH* game, a glaring
inconsistency caught my eye. Under the "Capabilities" section in
the equipment descriptions were discussions on the superior and
inferior systems each Mech and vehicle utilized. However, these
descriptions had no real effect on the game. This was not only
disappointing, but it also made certain 'Mechs and vehicles inferior
to others because their complex systems had no effect on which was
doing a better job. For instance, the Rifleman and JagerMech 'Mechs
were both praised for their abilities as antiaircraft platforms. But
I would much rather have an Archer or Marauder 'Mech taking on
aircraft, because in the actual game all four 'Mechs have the same
chance of hitting the aircraft, and the Marauder and Archer would
do much more damage on a successful hit.
So, I have created a list of modifications for all the 'Mechs and
vehicles for which I currently have the statistics and in-depth
descriptions (all the 'Mechs and vehicles presented in the two books
listed above). The modifiers given are listed for each dieroll target
number, not the actual die roll. This system concurs with that
presented in the BATTLETECH Manual: The Rules of Warfare.
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BattleMechs
Light Mechs
Commando: None.
Firestarter: None.
Javelin: A piloting skill check at a -1 bonus is required when running
through rough terrain, rubble, or woods.
Jenner: This 'Mech cannot punch because of its arm design.
Locust: This 'Mech cannot punch because of its arm design.
Ostscout: This 'Mech has highly sensitive sensor arrays that can
detect heat, light, sound, etc., at a 90-km radius. While in deep
scan, however, the 'Mech will not be able to warn its pilot of danger.
Another scanning mode can also alert pilots to the location of 'Mechs,
vehicles, large groups of men (10 or more within 10 meters of each
other), mine fields, and cities.
Panther: This 'Mech must roll 2d6 upon any successful punches with
the right arm. If a 12 is rolled, the heat output of the PPC increases
by one point.
Spider: All attacks on a jumping Spider are penalized with an additional
+1 penalty to their to-hit numbers.
Stinger: None.
UrbanMech: This 'Mech cannot punch, but attackers get an additional
+1 penalty on their to-hit numbers in any situation in which the
Urbanmech has partial cover.
Valkyrie: None.
Wasp: None.
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Medium 'Mechs
Assassin: The game master should roll 2d6 every time the Assassin
falls or is hit in its left torso. If a 12 is rolled, the SRM 2 ammo
jams and will no longer feed into the SRM, although the round currently
loaded may still fire. This jam can only be repaired in a fully
functional 'Mech repair bay.
Blackjack: None.
Centurion: None.
Cicada: None.
Clint: All repair times are multiplied by 1d4.
Dervish: None.
Enforcer: None.
Griffin: None.
Hatchetman: The Hatchetman's hatchet does 9 points of damage, instead
of the standard 5 points of damage done by a normal punch from a
45-ton 'Mech. The 'Mech ejection system removes the entire head of the
'Mech, not just the pilot. This 'Mech also has a -1 bonus on its to-hit
number against aircraft.
Hermes II: This 'Mech's advanced communications system has a 1000-km
range and can communicate with spacecraft in orbit.
Hunchback: None.
Phoenix Hawk: This 'Mech has many optional devices available to it.
The GM should decide which of these devices he will allow the players
to have, as well as their effects and cost. See the "Capabilities"
section of the Phoenix Hawk in FASA's Technical Readout: 3025.
Scorpion: This 'Mech may change its facing at the cost of .5 MPs per
hex side turned. All "leftover" fractions are rounded up. For example,
a twohexside facing change costs 1 MP and a three- or four-hexside
facing change costs 2 MPs. These facing changes can be made at any
time during the Scorpion's turn in the Movement Phase. Any attack against
this 'Mech made by infantry in the same hex as the Scorpion automatically
gets a chance for a critical hit in each of the following areas: the
left torso, center torso, right torso, and head.
Shadow Hawk: None.
Trebuchet: None.
Vindicator: None.
Vulcan: All attacks on this 'Mech are at a +2 penalty to hit at long
range and +1 penalty at medium range because of the Vulcan's shape.
The Vulcan also has a mandatory heat gain of two, instead of three,
when jumping.
Whitworth: None.
Wolverine: None.
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Heavy 'Mechs
Archer: None.
Catapult: This Mech cannot punch because of its arm design.
Crusader: None.
Dragon: This Mech receives a -1 bonus to its piloting skill number
when rolling to prevent falling from massive damage and when falling
from physical attacks (inflicted or received). Attackers also gain a
+1 penalty to hit when firing at the Dragon from long range.
Grasshopper: None.
JagerMech: The JagerMech has a -2 bonus on its to-hit number against
aircraft because of its tracking system.
Marauder: This 'Mech has one critical weakness: the collar that connects
the pod-shaped torso to the 'Mech's legs. On any hit on the center
torso on the Back or Side Hit Table, the attacker should roll 2d6.
If a 12 is rolled, the Marauder either loses its ability to swivel
its torso, or its ammo train to the autocannon is jammed (roll 1d6:
1-3 torso cannot swivel, 4-6 ammo is jammed). If two successful hits
are made on the torso swivel, the 'Mech's movement is reduced by half.
If three such hits occur, the 'Mech loses all movement. If multiple
ammo-train hits occur, 1-6 ammo shells explode. Marauder pilots may
wish to add an improvised armor collar around the linkage. To do this,
the Tech may add up to 10 points of armor that strictly protects the
linkage. If this is done, the armor must be breached before critical
hits on the linkage only may be made. The pilot of the 'Mech also gains
a +1 on his piloting skill number per 5 points of armor (rounded up)
because of the weight imbalance created by the collar. Attackers may
aim at the collar as per the normal aimed-shot rules, at an additional
+1 penalty on their to-hit numbers.
Orion: The Orion's efficient design makes it very easy to repair, so
divide the repair time by 1d4. The Orion's missile systems also have
a -1 bonus on their to-hit numbers against aircraft. Unfortunately,
the 'Mech's LRMs might shut down because of their inferior cooling system.
When rolling for shutdown due to heat, roll separately for the LRM system.
Ostroc: This 'Mech has a +1 penalty on its to-hit number when punching,
and all attackers gain an additional +1 penalty on their to-hit numbers
when the Ostroc is in partial cover.
Ostrol: This 'Mech has 5km scanning and targeting equipment.
Quickdraw: This 'Mech may fire all its medium lasers rearward. The
Quickdraw loses 1 MP for each 8 points of damage done to its legs.
Rifleman: The Rifleman has a -2 bonus on its to-hit number against
aircraft because of its tracking system.
Thunderbolt: None.
Warhammer: None.
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Assault 'Mechs
Atlas: This 'Mech can communicate with ships in space.
Awesome: None.
Banshee: None.
Battlemaster: None.
Charger: None.
Cyclops: The Cyclops' communications systems allow for a planet-wide
sending radius as well as surface-to-space communications.
Goliath: This 'Mech cannot move if one of its legs is disabled.
Stalker: This 'Mech cannot punch because of its arm design.
Victor: None.
Zeus: The Zeus' LRM system has a cumulative 30% chance of failing each
month it goes without maintenance. This 'Mech's right arm punch does 10
points of damage.
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He goes on another page for Aerospace and Vehicles. Follow the link for those.
Many BattleTech rules (i.e. Partial Cover, Quad 'Mechs, and Hatchets) have changed since this 1991 printing, so use at your discretion.
See the full article here: http://dnd.ezael.net/~olep/Drmg166.pdf (pp 16-18)