Today (as of R#189) we have an unfortunate dependency on the PPU as the only supporter class in NC. In PvE this takes us to dual-logging, in PvP there is a tendency to deploy a battleforce made up of 50% PPUs, just to make sure every damage dealer is supported properly. This dependency is limiting the variation of playing styles and forcing players to cap APUS and LOM to PPU after.
This situation can be eased by introducing additional nanite tools. Right now there are TL 16 (see below) and 40 heal nanite tools, the latter still suitable for all classes. By adding nanite heals of (around) TL 60 and 100, PEs and tanks would be more independent from PPU support (while a skilled PPU player probably still would be preferable). To enhance this newly gained independence, we need new damage blocker nanite tools (also TL 60ish and 100ish) - comparable to already available damage blocker drugs and discontinued (NC 2.1) damage blocker psi modules.
The proposed new nanite tools would probably be found in hacknet databases, or at specialised vendors within BT and FA HQs.
Of course nanite and psi effects can only be used alternatively, so if you use nanite heal and damage blocker, you are no longer benefiting from psi heal and shields, just boosters.