It lacked flexibility. It severely cut down players option, much more than probably desireable. The maps where not made for it, at some times you had a Vbase and were required to take an enemy airfield with the next friendly airbase several sectors away (and yes, that's 'too hard'). And prime time, you had that few designated battle places and nothing else, which sucks if your computer wasn't made do handle that many cons. You couldn't make another plan, as there was only "smash THIS base" available, no bypassing movements, nothing. In the end, even less 'strategy' than we have now.
But you gotta give the players options. In my previous example it could be like "go for that 6 point large base" which is probably very well defended because of it's value, or try to take 6 vbases instead.
Or with the "central objective" variant, you have all the options where to strike in the beginning, but the firther you move forwar, the less desirable it would be to open yet another front.