I predict that you'll return to this thread after your vacation and say... yes, it was expensive, but you had a great time and can't wait to go again
I've done Disney with the family multiple times from around 2001. Last time we did it was 2017 but the kids are grown now so we haven't been back since then. First time I was like you - especially when I saw how much it was going to cost. But now, I only have great memories of the place.
When we started going, we didn't have the apps and things that are around now, so we basically planned it out from brochures, and looking online; We never used 'vacation planners', and the last few times we went, we never needed that service as we knew pretty well what we were doing.
We've never stayed in the resort itself, mainly to keep the cost down. We generally stay in and around the International Drive area as it's a lively place with reasonably priced hotels. All of the hotels from there run regular, free shuttle busses to Disney and the other attractions. Not been there for five years, so hopefully that's still the same!
Another reason for staying in International Drive is generally because we don't only do Disney when we go - we normally also get tickets for Universal Studios, SeaWorld, and Busch Gardens, too. Plus the missus liked the malls for shopping, etc.
We'd spend two weeks in Florida and probably visit Disney on four of the days, SeaWorld one day, Busch Gardens one day, Universal Studios one or two days, shopping on a couple of days, etc. In between each of these, we'd have a day or so just hanging at the hotel at the pool, or down I Drive, etc. It can be full-on, so we would need those days out just to chill, and plan for the next day!
If you're planning on going next year, then now is not too early to start planning things. To be honest, I've never booked the dining experience inside the resort, so not sure if now is too early to book. However, as you're thinking, a vacation planner will sort that side of things for you.
I'm looking forward to eventually returning to Disney with the grandkids lol.