Perhaps you misread my posts and we are arguing about nothing: I have only said that it would be wise for the OP to consider mirrorless cameras as an
option in addition to dslrs.
I own a dslr (a D7000), so you don't have to explain to me how much better a good dslr is in this department, trust me, I know. Every time I take out my dslr I can feel the difference. But for a lot of people the AF in non-dslrs have gotten so good that the advantages outweigh the downsides. That's why –
before giving my recommendation – my first question was what the OP intends to use his cameras for. And he didn't mention things like sports or other action-laden genres, and so I merely suggested to include mirrorless cameras in his considerations.
I cannot speak for all mirrorless systems, by my two Speedlights work just fine in manual mode on my Fuji, and I can even trigger my other Speedlight. Of course, I'd have to get a Fuji or Fuji-compatible flash to be able to use TTL, but honestly I don't need that. To get an idea how “difficult” it is to use a flash on a mirrorless camera, have a look at
David Hobby's strobist.