It's hard for me to understand the motivation to move away from a bag. I've been using a bag for about 5 years now and have tried all kinds of baskets since then and I hate them. I've tried kettle RIMS and occasionally brew on 3 vessel HERMS systems and while it's plenty fun, it's too long of a brew day and too much cleanup for my taste. Long story short, the more systems I brew on, the more a single vessel eBIAB rig is being solidified as my forever brewing method.
The primary pros of my bag system is that there is no system more temperature stable, or faster at doing temperature ramps. 4 hour brew days and one kettle to clean. I only brew 6 gallon batches, but my good friend has a larger version of my system and brews 12-15 gallon batches all the same. I think 10-12 gallons is comfortable enough on a hoisted bag system. Above that, I'd probably go 3 vessel.
Don't underestimate the complexity jump of a 2 vessel kettle RIMS or 3 vessel HERMS. It's significant.