Thanks!
I think I'd first send your DH a "support link" (aka "prefer" minus the p because the mods are weird about the "r" word

) to your DH from your CSP for him to obtain a CSP-that way you earn a bonus and he'll earn the SUB which is 60K right now for $4K spend (not the highest, historically but not bad). If he's approved you'll earn 15K so together that's 75,000 Ultimate Rewards which are good for Southwest (domestic flights) as well as transfer to Flying Blue/KLM (which can get you to Europe from DTW) or United (flights from ORD). I'd then consider the freedom unlimited for the 1.5 multiplier for the remaining spend-right now the MSR is $500 for $200 back (or 20000 Ultimate Rewards plus the $1000 spend so another 1500 URs which then can be transferred via your CSP-chase sapphire preferred) to either Flying Blue or United (or Marriott, Hyatt, etc...) when you need them. That's the first $5K spent. Obviously I'm looking long term at stockpiling URs for Europe flights-those usually open 11-12 months ahead of time AND don't expire if you keep them as Ultimate Rewards and don't transfer to the frequent flier programs.
It can take a lot of miles/points to get to Europe with an entire family so collecting slowly and keeping them for that purpose takes some discipline. The above play should earn your DH 64,000 (SUB + 4000 from spend), 36,500 for you (SUB+spend+ 15000 from the
preferral). So once y'all combine that should be 100,500 URs. Economy saver awards from ORD-MUC (or other locations in Europe) begin at around 30-33k/pp/one way (but can be as much as 70K for nonstop) so you're looking at almost getting there for 4 with that haul. Flying Blue is a little less predictable but I've found 2 A 2K 1 way from DTW to CDG for 52, 500 flying blue miles next July so depending on your dates 100,500 URs could get you a RT to Europe.
Anyway, those are my thoughts...fortunately you're going to have several tuition payments to make so can tweak as necessary, although please keep Chase's 5/24 in mind because that is definitely a rate limiting rule!