To make sure we're on the same page:
The modules don't mimic the techs, System techs also need the modules, they just get more milage out of them.
(From both the general and specific perks.)
Regularly? No.
But I made a piont of just completing a run with a sys.tech hero, for comparison's sake.
They are underwhelming.
At first I thought I'd use a sys.tech. as my tank (instead of an ace), using his 150% (total) repair bonus and 4... Just blanked on the name. 10 hp/sec teamheal module (when the solo best - nannite - is 8 hp/sec) in a Trident.
Took too long to get a good enough repair module for that to work, and by then I had enough accurate damage to not need that kind of tanking.
Ended up using him as an ams for most of the game, when I finally switched, an unskilled pilot using a cerberus (best ams module) had the same results.
Not only that, my sys.tech. With 3 teamheals couldn't keep a focus-fired teammate alive against gen4 enemies.
Tl,dr - whine whine blah.
I *believe* that the problem is that enemy wings don't have the 'guru' perks, so between low base ecm penetration (low-gen missiles) and low pen-bonus, you're essentially safe from missiles if you have an equal-or-greater ecm.
Also, you need to walk a line between repair being useless and godmode.
(of course, if you wanted to cheese you could just go full-out stealth, but meh.)
Also also, with total repair and shield regen ending up at 150% and 125%, respectively, the added maxenergy that shields grant (at the cost of half their regen rate) make them better than an equivallent repair module across the board.
The difference is that shield are solo-only, but given that a maxed out repair pilot won't save you *anyway*...
All of which is why I was going to split shields into 2 components.
At least, once I finish hunting down all the things that need to be edited.
That's my take on it. Sorry for the tl;dr.