Money will always be there, but with Florentino goes some of the power and influence Real Madrid have. You never know if the next guy is competent either. Might end up with someone like Calderon which is clearly a downgrade.
Sure, there'll be a big shift. Question is what Perez's mission really is. From 2009 onward it was the league and Decima, then it was keeping that 2015-2017 dominance period going. But somewhere along the way he was casually creeping on with the stadium - something that will unquestionably be 'his' mark on the club. I don't suspect he wants to squander it all as fast as it seems to be going right now so in my mind he will be here for what I suspect will be nearly another decade. His mission is to set the club up against the sheikhs who are younger and have deeper pockets. The only way to do that is to bring the club back to the basic level where a certain generation of fans who came to watch the games for one reason only - to see the big stars perform. He seems to want them filtered out. He needs to establish a basic level fanbase that will stick with it under circumstances of minimal expectations with:
a) 1 world-class player (then Ronaldo, now Bale experiment, soon to be Hazard, then probably Neymar/Mbappe) who will carry most league scores
b) ... surrounded by local Spanish youth (hence he was preserving relationships with teams across the league, be it Sociedad, Betis or even Atleti and Seville)
c) talent scouted from South America who, if all goes well, will convince the next generation of players from the continent to join
d) ... connecting it all it seems it will be Pochettino who worked with almost the same recipe in Tottenham except he started with even less (had to make Kane into a world class forward).
Lots of risks, lots of uncertainty, lots of things could happen in the next 10 years. I don't think he feels he's done everything as a president. Another 5 years seem to be on the cards, assuming his health holds up. Only once he's secured all 4 and there is little doubt what else he could do better, then he'll leave. ATM even a few of these younger options (Vallejo with injuries, Theo possibly being a scrub) are still being reevaluated so he's not done yet.