Atm we got plenty of variants. It should be easy to find a few that suit you.
The main concern I would have with the Mechlab (others might share this thought), is that it would promote boating of the "strongest" weapons and equipment.
Right now this would mean UAC20 and GECM everywhere.
Or some flying fortresses with BxP, ELRM and NARCS.
I think everyone is worried about this.
I hope what'll happen is that the mechlab doesn't make it in until very late in development, and even then it's
very restrictive. Perhaps something like:
you can't modify empty chassis, only variants.
You can only fit a gun to the matching podmount (so an assault class energy hardpoint can only take assault class energy weapons).
You can't fit multiple weapons on the one podmount. One podmount = one gun.
You can downgrade podmounts to a smaller one of the same type, but you can't upgrade them to a bigger one or change the podmount type, and you don't get any extra tonnage from taking a smaller podmount (though of course you will get extra tonnage from taking a smaller weapon).
If omnimounts are used at all they should be used sparingly and still shouldn't be able to take more than one weapon. The only difference would be that you could take weapons of any type (energy, ballistic or missile). You'd still be limited to one gun and you couldn't fit a bigger gun than the mount would allow, no matter how many tons you had.
Equipment options (JJ, GECM, BAP etc) would be limited to chassis type or even variant. Perhaps you could add add them on some variants or take them off to get a few extra tons, but you wouldn't be able to just whack them on anything. I'd also like to see equipment taking up more tons for heavier mechs, or the "take GECM for 1 ton" option is going to be a bit of a no brainer on a heavy mech.
So if you had a variant that mounted 1 ERPPC and a AC20, you could perhaps downgrade the ERPPC to a PPC in order to free up tons to swap the AC20 for a UAC20, but you couldn't, for example, rip all the guns out in order to cram 8 MBLs in. You could even swap the assault energy podmount out for a heavy energy podmount so you could take a LBL instead of the ERPPC and use the extra tons to take a UAC20 and several tons of spare ammo, but that'd be about as far as you could go.
That way boating could be discouraged by making variants that simply don't allow the player to cram a lot of weapons of the same type in in the mechlab.
EDIT:
I am not really sure I understand the fear of boating that all of you seem to have. You might maximize fire power but on the same note, you minimize utility. Every weapon in this game has it's drawbacks.
I think most players would be cool with boating if it was really no better than mixed setups overall, but right now the preference for boats suggests that boating has more advantages than disadvantages. If this can be "fixed" even with a mechlab then that's great, but I'm not sure any mechwarrior game to date has managed to allow boating without also making boats the better choice on balance than mixed weapon configs. If MWLL can pull it off then that's awesome, but if they can't I'd rather see boating discouraged through other gameplay means.
