Something I'd like to see added to the abilities...
Give Martial Arts a third tree, call it "Melee Weapons," that would compliment the MA tree. I don't even use MA and I think it would be sweet for people to have access to katanas during a fight. Have an actual katana as a weapon, but only usable through the level 24 (?) ability that you load in the tree, much like Dual Handguns, SMG's, and Sniper Rifles.
This would be like a reflection of Sniper in the Gunman tree. Level increase or not, it would be sweet to see this added. While there are balancing issues for new abilities, it would even be nice to see "Weapons" or "Swords" as an additional tree to use. It might even be nice to see an additional MA style like "Drunken Boxing," or the addition of a Gunman tree called "Heavy Weapons," like the Howitzer or Network Attacker of the Gunman trees. The SMG's just don't cut it for me as a crowd control build, but an AoE weapons blast with an 8 second re-use timer would. Keep it Ballistic, even, and it still wouldn't be overpowered. Most 50's have good ballistic resistance.
As another idea, how about a new Coder tree built for defensive purposes? Use code bits as materials for creating brief, yet powerful buffs or shields in an area. Hell, this could be done even without code bits. But the whole purpose is quick, powerful bursts of coding to add to an area. Maybe you offer +60 to defenses for 12 seconds, enough time to lessen damage on your allies for a few hits. This could easily turn the tide of battle, someone loading this. How about giving a sweet accuracy buff for 12 seconds to everyone within six meters of you? What would be fair? +20 pts? +30 pts? Nothing too extraordinary, considering the time its active for.
Just ideas, but additional trees that would compliment the existing trees would allow the level cap to be raised, if that's what we're constructively trying to perceive.