The Kit Fox is probably one of the hardest mechs to use in the whole game. The Locust, Commando, Spider and Jenner are fast strikers, and in that role, they all are pretty effective, the Raven is premier scout and ECM support, the Adder seems to be powerful fire support. Hell, the Locust works in its role quite well in skilled hands though i admit there are better options.
The Kit Fox? It lacks speed to replicate the striker role, even a lowly Locusts is better at that. Nor does it really have speed for scouting either, despite the ability to mount an ECM, which may be an detriment as it makes it a high priority target. Its low slung weapons make it a weak sniper. It is weak, though mere 1.5 tons of armor is enough to maximize its protection, this is taken from the nice 16 ton pod space, and given the mech's short comings, it needs everything it can have for weapons to make most out of the chassis, i think. It does have ECM and jump jets but leveraging those in combat is not easy.
One thing to note is that as long as you don't mount energy-heavy loadout but a mixed one, the mech runs relatively cool even without additional heat sinks. It can fire quite a lot, and it still has quite good mobility to get to cover to cool down.
All these make it a very challenging to use... one i find very, very appealing. I like being an underdog i guess, the extra challenge. Makes victory so much sweeter.
For me, the ideal playstyle is a generalist fire support. Mixed weapons loadout, such as Prime or alt config B, ability to engage at variety of ranges. Move with others, target their targets. I often make the mistake of attracting attention, i am and always will be something of a lone wolf... But when i don't screw up, the mech works pretty well as it has rather high firepower for its size.
Interestingly the mech seems to work pretty well in close quarters combat, in general melee. It seems people prioritize heavier targets in such fights, and that's were light mech with high firepower shines. As long as you can avoid getting shot and avoid attracting too much attention.
As for the low armor, that doesn't really bother me. It is not like maxed out armor would offer much more protection. I reckon the Kit Fox needs a kind of savage mentality, a berserk mentality, if used for combat. Hit hard, dodge as much as you can and hit again, being aggressive and deadly is the best defense.
Guess it could be a support player's mech, with TAG; ECM, and some missiles for fire support, a role where the weak armor doesn't matter that much either.
Jump jets: One jump jet still allows fast turns, if you can do that. I can't do it well enough for it to be any use, too risky for me. Besides, as i said, mounting less than 3 JJs offends my purist-sensibilities, pretty sure 3 is the least amount of JJs any mech in the Battletech mounts.
EDIT I write way too much. I should analyze these somewhere where there are more readers, not GAF, pretty sure we don't have even a ten players here. Of course the alternatives would be Mechspecs (registered, post some but only little), where i would face some competition by more dedicated players with numbers and stuff (and possibly a bit more meta-oriented attitude), or the official forums... and my opinion about any game's official forums is that they're the worst place to talk about the game.