To me, while looking at the developments of the past 10-15 years, it seems china wants to catch up with the western world. If we go along with that assumption, it becomes apparent that china can not afford to have life cycles of their planes be as long as ones in the west. As we speak, there should be preliminary designs worked out so that, after a hefty development phase, j-10 successor can start being fielded by 2020.
If that means just 500 j-10s built until then, so be it. Though that is another huge issue, really - the low rate production that seems to pester every single of chinese plane producers. Chengdu seems to be the biggest, no? But now its production capacities will be making 3 types of fighters. Wouldn't it be benefitial if at least j-7G version went out of production and made room for j-10? Or even FC1, so then once that is out of the way those production capacities can be added to j-10 ones.
I find it unacceptable that chinese seem to be pursuing high, low, super low mix of fighters. Sure, in transitional periods it is always like that but i think it is actually more costly, in the long run, to use 3 diff fighters and maintain production for them. High-low mix is quite enough.
Also, goverment support is taking some efficiency away. Too many plane producers getting help. It is a priority that many of them merge and that china is left with preferrably two but at most 3 plane producers who would then be true competitors for govt. programs.
Overall number of diff planes would go down then, of course, but that is a good thing. Close air support or battlefield interdiction as it is done today should be a thing of the past. Way too dangerous. Instead use precise munitions and any fighter-bomber can do it. So q5 is out of action. When numbers of j10 and j11 are enough (assuming j11 are gonna get another licence contract for 100-200 planes as j11b) remove ALL the j7 and j8. What one would be left with is then j10, j11 as fighters, hi-low mix where high isnt necessarily better tech but just larger size and all the benefits size brings with it, jh7 as a strike plane for both PLAAF and PLANAF and then h6 as missile carrier, unless some better plane can share that role - transport plane or airliner.
US, for example, is making huge steps with each new generation of planes. But it takes them 30 years to make each step. And it costs them A LOT to be ahead of the curve. Why not be slightly behind them on that curve, and instead of making monumental leaps with each new generation, make slightly smaller steps, but launch new plane each 18-20 years? In the short term, yes, it might even be a bit more expensive, but not only would you have a more responsive force to the needs of the era but in the long term your technology base would grow faster, better, less prone to mistakes than with slow, huge steps. I just hope there will be money to fuel both the j11 and j10 successor at the same time.