So generalize it a bit. Maybe you select either repair all or repair except weapons. Then at the end of a match the various things damaged have a "cost" that is a % of the payout. It can be a line in the total - repair and refit costs.
Lights might only add up to 35% of the pay out even in a worst case, all arms and legs blown off scenario. A lost worse case assault maybe upwards of 60%. Gives an incentive to drive cheaper mechs - less is at risk. Also ammo from LRM spamming mechs will reduce your payday over a set of handy lasers.
Beginners might be exempt for 20 matches. Faction loyalty awards could be covering some of your R&R costs so your pay outs go up.
Edited by SuomiWarder, 15 November 2014 - 10:34 PM.