OOF I started a reply here, but got caught up between work and the Switch2 release to finalize and reply
VGF one-bedroom availability, especially preferred view, isn't too bad outside of the holiday season (Thanksgiving to NYE) because one-bedrooms require so many points. Same with dedicated two-bedroom units.
Lock-off two-bedrooms are difficult because deluxe studios are in high demand. All the new Big Pine Key points made booking deluxe studios even more of a challenge, especially at popular times of the year when the
points charts are low.
If you'd always be happy staying at RIV, then adding more RIV may honestly be your best option. That is how I feel about VGF. I would never be sad if I was "stuck" staying there. If it were the same price as PVB right now I would buy it direct no questions asked. I am trying to convince myself PVB IT may not be bad since it's basically in the parking lot of VGF and I could probably get VGF resort studios, especially preferred in the spring. Then another part of me says I would rather guarantee myself the larger VGF units for the exact dates I want in the home resort booking window and I look at the resale contracts in disappointment (price, points status, ROFR, etc).
I do think it is good to explore the MK resort area first because RIV is only one
DVC resort. There are so many options and the monorail resorts are great, especially for rope dropping MK, closing down MK after fireworks, hard ticketed MK events, or just casually watching fireworks from your room or resort. I had stayed at all the WDW deluxe resorts except AKL so I knew what my favorite area was overall before committing to it. If a walkable Crescent Lake pops up with 50 years I would buy that too, but not as many points as VGF.