Two questions here:

1. I have an upcoming trip IAH-IST-VCE booked in J, with a stopover in IST. On part of the stopover we will be making a side trip to Bodrum. My question is if I book the BJV-IST flight on the same day as the IST-VCE leg, how much time will I need in IST to deplane, collect our checked bags, go through passport control(?), etc. and leave enough buffer to comfortably make my VCE flight? Options are 3.5 hours or 5 hours buffer in between landing and departure.
2. On the return trip VCE-IST-IAH they only gave us 65 minutes to make the connection. I am noticing on flight tracking websites that the VCE-IST flight (TK 1868) is often delayed at least 30 minutes. Given everything I've read in this thread, it sounds like 65 minutes is really not enough to make the transfer if the inbound flight is so delayed. On the other hand, flight tracking websites also indicate that the IST-IAH flight (TK 33) is often delayed as well, especially on the same days that TK 1868 is delayed. So maybe they will hold these long-haul international flights to wait for all connections to make it? Anybody think I have any cause for concern? Should I proactively try to switch my VCE-IST flight to MXP-IST, which arrives 2h15m earlier?