Here's my current recommendations for a first mech:
Light:
Jenner - It's much cheaper overall to upgrade and most components are transferable between variants. JJs are invaluable in the current meta.
Spider (alt) - The skill requirement is over the top high, but if you spend on both a XL255 and a STD 250, you should be fine. This isn't recommended for beginners.
Medium:
Hunchback - All the best builds can easily be covered by the cadet bonus. STD engines are required for survival, but most benefit from cost considerations. The only skill consideration is with the "hunch" where you will suffer greatly if you don't torso twist and become a support player... because mediums are unforgiving in general.
Centurion - This is probably one of the few mechs that can't be easily be one-shoted unless you keep staring straight into the opponent. The only expensive variant is the Cent-D, but the best builds on the Cents overall require STD engines. Torso twisting is imperative to keeping weapons operational and allowing long range/stronger weapons to stay effective (Cent-AL with PPCs or LLs or the Cent-A with a Gauss Rifle benefit from good torso twisting). Otherwise you will be limited to short range which is where the mech thrives for the most part.
Heavy:
Catapult - You can survive on the default engine you get on all builds (STD 260), so you can minimize your costs. It's probably optimal to start with the K2 since you can work on your direct fire skills whereas the other variants will require other skills... the only major issue is the cockpit, which can be a source of fustration.
I have no alternative options for heavies, as they have various different weaknesses and associated costs that make them wholly undesirable as an initial mech... maybe a Cataphract (focusing mostly on the 3D, but even then...)
Assault:
Stalker - This sounds like some sort of 4 PPC recommendation, but it's not. For the mech to be functional, it must be running a STD engine and those are a lot more affordable (you'll probably want to get a STD 270 or 300 at some point). The primary focus is all around heat management and building a mech that addresses that (don't be surprised if most loadouts must have a total of 20 DHS).
I have no real alternative options for assaults at the moment, but I'd have to see the Victor's c-bills costs posted before I can see viable options (I mean, they come with a STD 320 by default, so you might be able to do stuff with that).
Edit:
One more mech that I had kinda reconsidered was the Cicada. If you go for the Cicada-3M first, you can build something relatively simple and reuse the XL320 that it comes with on the other variants. The STD 320 on the other Cicadas are great for a future Assault mech (well, specifically the Atlas) or could be sold outright for a bit of cash. It does suffer from being big though.. but you are most effective when you use it like any light mech (because... it is an overweight light).
Edited by Deathlike, 10 July 2013 - 01:55 PM.