I like Thybulle. I've been watching him for two years, thinking he would be good for the Spurs. This time last year, about the only discussions you'd read about him were wondering if he was undraftable. I never saw any talk about him possibly going in the first round until the last few weeks.
My biggest concern is that he's 6'5", and the Spurs are already loaded with players about that height. I did a search for active players, over the last 3 years, who are 6'5" and have a 3P% of .310 or less. The list is short - 39 players. And by far the best on the list is DeJounte Murray. Most are dogs who barely have any minutes in the NBA. Take the 3P% up to .330 and the list only grows to 45 players, and you see players like Jeremy Lamb, Jordan Clarkson, Kent Bazemore, and D'Angelo Russel. The point is that 6'5" players who aren't PG's and don't shoot the 3 very well are going to get passed over by a lot of teams in the draft. Thybulle is an exceptional defender, and the reason he's getting any first round consideration is because of people thinking Kawhi Leonard. But he's nowhere near the offensive player that Kawhi was in the season before the draft.
I'm a fan, but I have a hard time seeing him go higher than the Raptors' pick. And the only reason I see there being room for another 6'5" player on the Spurs' roster is because his reach and strength may let him defend some bigger players. If Chip can fix his 3P shot, and he gets up around .400, then he's a bargain. If not, anything above late first round is going to be called a mistake. I know that a lot of people seem to think that improving a 3P shot up to 40% is something anyone can do - especially with Chip coaching them. But it's just not that simple.