I've never felt limited with PADI tech. My only bug bear is the redundant buoyancy issue - but that's hardly uncommon amongst agencies.
I felt quite limited teaching recreational courses - but mostly the rigid standards occur at OW level, IMHO. I've run AOW, Deep and Wreck courses to my satisfaction for years. The only drawback on deep and wreck is the amount of 'wasted' dives. Yes, I fill them with good buoyancy, team and situational awareness development - but they could be so much more (by standard).
I don't like any tech agency that sets a too low bar on instructor entry. PADI aren't the only ones guilty of that. It tends to 'cheapen the brand', the perceptions of such are evident in this thread. The biggest problem, IMHO is the process of using Course Directors to certify technical instructors. Many aren't technical diving specialists (by experience, or passion). That's a problem for any agency that mixes recreational and technical diving. PADI should soon be allowing direct upgrade to Tech I.T. without CD requirement (they already did this for cross-overs, but not internally). I think that'd be a good step forwards (potentially, if not abused).
Instructor-Trainers are the key to maintaining good technical instructor quality. PADI has a deficit of experience at that level, IMHO. Thus, people qualify to teach who shouldn't... it becomes the stereotypical 'tick the box' exercise for training... and less about a true expert ascertaining expertise in their trainees.