It appears that the current hardpoint system is much too simple for the complicated arrays of mechs, weapons, armor, engines, etc.
With the current hardpoint system, you are penalized in several ways.
1. You are encouraged to place the largest weapon available into a slot.
2. You must take double heat sinks to compensate for the large weapons
3. You must maximize your burst damage in order to compensate for your high heat
4. You must find the most effective way to hide while your heat dissipates
5. Whatever else, tired of listing things
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Hence the arrival of the poptart, and boating. The pattern reemerges with whatever the flavor weapon of the month is.
While in themselves there is nothing wrong, and there are ways to get around each strategy, it's indicative of a system that cannot handle the complexity of this PVP game.
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Unfortunately the way to fix it may be an overhaul of the system or a modified version like what I would outline below.
1. Each mech should have a different number of available slots in relation to their weight.
As it stands now, a commando has the same available slots as an Atlas. Which means, if you can find the weight, you can put a PPC or whatever on it. Or a raven with a gauss. Or the other extreme of a 90ton Highlander not being able to hold an AC20 on it's arm even though there is a ballistic hardpoint there. (except for one variant)
Engines should have slot amounts proportionate to their rating.
OR
As an alternative, have the weapons change slot size based on weight class. So instead of a LL taking up 2 slots, on a light it would take up 3 or 4 or however you want to balance the system.
Of course this would upend all current variants of all mech types, and mess up the current mech XP system.
2. Eliminate quantities of hardpoints, but allow hardpoint types.
What does this mean? Designate what kind of weapons are allowed on a mech area. Missles on torso, ballistics on arms, as an example, and leave the qty of weapons up to the player.
This would allow the mech models to stay the same, and not penalize for placing or boating smaller weapons to compensate for having a few larger weapons.
Add this feature to the number of available slots for a weight class, and you effectively eliminate boating of massive weapons, but allow boating of smaller ones if slots and weight allow. Lots of small, or few large.
3. Engines should have an energy rating that all weapons tap.
This would eliminate boating too much energy and being effective. It would also keep a smaller engine mech from putting out insane amounts of energy that the large weapons use. If you don't use all the energy of the engine, let it affect mech speed, and energy weapon recharge rate. Alternatively let there be a penalty for taxing the engine.
Missles and ballistics would have energy use as well, though it wouldn't affect reload speeds since it is a mechanical system.
There are lots of other little things the game does, but these three points would fix the current system. Maybe some of them are redundant with weight, such as Engine Energy, but it's something to discuss.