Considering going full frame, but one major issue...

... The lenses. Or rather their quality and how much you have to spend to get something to deliver the promise of full frame.

I've owned cropped sensor DSLR's before and I'm big on mirrorless cameras right now. Full Frame wouldn't be a replacement to my current gear, but rather to compliment it. Its uses would be mostly indoors, shooting kids and limited to 35 and 50mm primes. The edge of AF speed and added details and subjective bokeh are big incentives for that move. The new and relatively affordable Nikon D600 helps too.

But when I actually read user experiences, AF speeds vary greatly between lenses and if you buy,  for example, an inexpensive 50mm at F2.0, you're likely not going to get much IQ shooting wide open, negating the very reason why you bought the prime lens in the place. You can get the primes which perform as they're supposed to do, but you have to spend big bucks for it.

This is in sharp contrast to my current experience with mirrorless. If I take the Lumix 20mm, Zuiko 45mm or 75mm, you can shoot wide open, get great IQ and only stop down for creative purposes. Now there are some lens duds on mirrorless, but you don't have to spend a fortune to get some good ones.