Following is my personal opinion. Someone else's taste may be different:
Light:
Uller- If you own Firestarter, buying similar Jenner would be a bit pointless.
- Spider trades firepower for speed and jump capacity, but it's similar.
- Locust and Commando are very light, although you may have fun with them. However, they can't jump.
- Raven is a nice 'Mech (and I like taking it), but with the abundance of ECM in the game it's more and more difficult for Raven pilots to do their job. You can modify it as the pure combat-oriented machine, but Raven has quite big hitboxes and especially big legs.
- Puma is 5 tons heavier than Kit Fox and can mount more weapons, but its lack of ECM disqualifies it.
So my suggestion is
Uller.
It has many advantages: ECM, serious firepower of Clan weapons, JJs, durability thanks Clan XL engine. You can swap Omnipods and that's a big advantage, as you can mix them to mount lasers, autocannons and missiles.
If you are a team player and expect enemies with many LRMs, you can mounts up to three AMS with ECM and everybody in your team will be grateful. Just don't expect to play it as traditional Lights -
Uller is no speed demon, but a team player.
Medium:
Shadow Hawk /
Ryoken- Trebuchet is weak and fragile
- Centurion is weak
- Kintaro can pack serious missile/laser firepower, but it's big and has no JJs.
- Blackjack is small, even though you can make some interesting configurations. Vindicator is in similar category
- Wolverine may have its uses, but it has never catched my eye in the game.
- Griffin is not bad, but again you can mount only missiles and lasers
- Nova is quite "broad-shouldered", so to speak, and it is limited to lasers/autocannons (although Clan ones)
- Cicada is very fast, but the majority of its models is limited to energy weapons. People usually play it is ER Large Laser/ER PPC sniper. It can mount ECM. Sadly PUGs usually run away to snipe while the rest of the team suffers LRM hammering
Shadow Hawk has diverse models, so you can use configurations based around energy/missile weapons, energy/ballistic weapons, etc. It's quite fast and has good body shape.
If you can wait four weeks,
Ryoken will be available for C-Bills. It's probably the best medium 'Mech in the game. ClanTech, Omnipods, etc.
Heavy:
Madcat- the perfect blend of speed, firepower, armor, customizability and JJs.
- Cataphracts used to be great, but with standard engine they may lack firepower or speed while with XL engines make them vulnerable to side torso loss. They are still quite good, just they are not stars of the show as they used to be
- ditto for JagerMech
- Orion, Catapult, and Thunderbolt are average 'Mechs
- I consider both Dragon and Quickdraw to be quite weak 'Mechs: Dragon has very pronounced CT, while Quickdraw is just overgrown medium 'Mech (and again, you are limited to missiles/lasers (unless you buy Hero variant)).
Assault:
Daishi- Daishi will be available for C-Bills in two weeks.
- I wouldn't take Awesome as it is very broad - it's almost impossible to miss it. As enegy boat it suffers because so-called DHS work with 1.4 efficiency only. As LRM boat it needs spotter and no enemy ECM, if possible. As short-range brawler it's very big, for what it can deliver.
This is my personal opinion, so other people may suggest different 'Mechs.
