This is a good argument and I don't really have an answer. My question for you is this: if you gave a permanent unlock to warzones or operations, how much would it have to cost? I just don't see a feasible dollar number that anyone would agree on.
Now if it was a month, or three months, or six months, maybe...but Bioware has to keep bringing in money, and if you unlock warzones for say $15 or $20 (anything less would be a complete joke) by the second or third month they are losing revenue because you never need to buy anything ever again. It's just not realistic IMO.
I agree that currently the model is disconnected because it's trying to give subscribers value to keep their sub. But I think that their thinking is flawed.
Lets say that 10 dollars per warzone would be fair. (I know you suggested more). With 4 zones (don't know if there's been more since I left), that's 2 1/2 months worth of subscription revenue per person who wants to unlock.
Apply that to flashpoints and ops (maybe 5 per FP/OP) and maybe 10 dollars per endgame areas (there are 3 right now that are for 60 content, correct?), you'd have to purchase 19x5, 3x10 or 165 for just zone unlocks, or 11 months sub just to unlock everything at endgame currently. I think that's more than a fair tradeoff, most people won't be playing for 11 months and you are getting a huge boost of revenue.
That's just content too -- you also have people unlocking cosmetics, bank slots, and other goodies just to make them equal to sub players. Plus, sub players get guaranteed access to new content at no additional charge and a monthly coin stipend. Yes, not everybody will unlock everything, but if you intelligently place content on the store you give both sub players and f2p players value. I don't think they are currently thinking about that in a way that makes sense.