You should sell the kids

JK. I still find myself dragging adult kids along now & again & enjoy treating my GD.
Orlando is very expensive, moreso with kids!
Split trips are higher as both major parks have structured tickets/DPs & ME @ WDW to keep guests onsite.
I'm a type A person, get bored in one place on vacation and do split trips. Retired, I am lucky to be able to visit often via cheap airfare in my market. Eight days onsite, especially without FOTL perk, may be a necessity depending upon the time of year.
Everyone has a certain disposable income, how they choose to spend it is their business. I find myself often explaining to those that ask how do we 'do it'. we spend the bulk of our entertainment budget on travel. Many friends & family prefer to go out to eat several times a month, drive new cars every two years, live in a McMansion & then complain they have no $ leftover for travel. There is no right or wrong but i find people surely aren't shy commenting on other's personal business or lifestyle choices.
We are fortunate to own DVC (which i slowly saved up for over the years & added on slowly BTW) that affords us various discounts as to tickets/rooms. Even then, we often book room only onsite @ WDW. The price i just paid for the 2nd week there in October via a promotion is frightening indeed. Same to be said for availablity @ both parks. It's a business, they will charge what the market will bear.
The APH @ Universal helps you out with discounts, make sure to price out your hotel room via the discount. Possibly, you could find a good rate at one of the properties that offers the FOTL perk. You can then add on just one. Check out the date/rate thread here for what others have found & the historical pricing in previous years' threads.
Good luck planning your trip.