It can be tricky to get kills as Mechs are very tough, just focus fire on specific parts. Someone who pick their shots instead of firing at every opportunity (even if all those shots hit) will kill more mechs. I find Lasers are best for killing, AC's tear Mechs apart, PPC's and LRMS do consistent damage over a range of areas.
I'm having fun in my ridiculously pointless mech, the 4 Flamer Jenner. I can't kill anyone, I get lots of assists for 1 or 2 xp but it's funny. Oh you fired a PPC, why don't you shut down now.
If you're in the Beta hit me up in game and we can cruise around a bit.