I really suggest at least a transition with a half-court press, since the team knows zone, this first season anyway.
If you’re committed to full court press in the long term, flex works great with that (as it does with a 3-2 zone). You can utilize lots of speed and perimeter, which the flex emphasizes, at 3 positions, and even stretch the 4 if you want, as long as they can rebound a little; the press wants speed everywhere, so that works. The big thing you’ll want to think about with FB, beyond the fact that you’re giving up a season+ by changing both sets, is that you will always need full rosters. You’ll need to have that mindset in scouting and recruiting. No walkons, no redshirts, no ineligibles. And no guys who won’t get up around 70 stamina by the end of their soph year, at least not more than a couple. You generally want to shoot for close to 80 stamina team wide, which will be a hard pull starting out. But you’ll lose a lot of games, especially if your IQ is low in both sets, until you get there.
On the flip side, you can feel better about taking a few more guys you might normally want to look past, reach down a little lower, as it’s more about complete balance than pulling down high level stars. So it’s something to think about. Dayton is on the list of teams that need to watch out for the firing axe though, so there’s also that. A rebuild can’t take forever.