Going to go with a slightly different format to try and conserve space. I'm basing it off a mix of the 3025 Revised TO, 3039 TO, and mechs from the 3050 TO that were already in use in 3049.
Light: Flea, Commando, Javelin, Urbanmech, Panther, Firestarter, Hussar
(Never piloted a Panther due to heat and reliance on the PPC, but I appreciate it. Didn't put in the Raven because I didn't see anything saying it was available before 3050, and I put in the Urbanmech to improve my odds of getting a Charger. If there's a light wannabe assault mech maybe they'll put in an assault wannabe scout mech!
)
Medium: Assassin, Clint, Crab, Dervish, Enforcer, Hatchetman, Trebuchet, Vindicator, Vulcan, Wyvern
(Mediums are my favorites, especially 55 tonners, but few are shown here. The styling on the Wyvern makes me think of Mike Mignola's artwork. And the Vulcan would probably suck in game but it's still one of my favs in TT damn it.)
Heavy: Black Knight, Champion, Exterminator, Grasshopper, Guillotine, Jagermech, Lancelot, Orion
(Yeah, I'm a 2750 fan. I wouldn't want the Blackjack in it's 3025 layout but big-brother Jaggermech will do!)
Assault: Awesome, Charger, Cyclops, Hatamoto-Chi, Highlander, King Crab, Stalker, Zeus
(Charger for reasons stated earlier and especially if they add in close combat later. The Cyclops is to commanding as the Raven is to scouting so I'm surprised more people don't talk about it here. The Hatomoto-Chi was supposedly in Kurita service in numbers since 3039 so I put it in and so was the Mauler, but I don't like the mauler and the Hatomoto-Chi is a refitter Charger so it gets bonus points. lol)
I left out all of the mechs that have already been revealed and the Unseens, which I really want in the game despite not mentioning them. They made up the best of the 55 ton mechs (except the Dervish that sexy beast). I also left out some mechs that were only really in use by Wolf's Dragoons and even in 3049 were only piloted by 1 or 2 people in each house outside their company. I think an Annihilator would be far too rare to put in the game for another year when the IS's war effort is in full swing.