I never thought I would meet another person that loved the RP2+ dpad as much as I did! It’s pretty amazing imho.
I should mention up front that I hate the Steam Deck not only as a device, but also its controls (two deeply unpopular opinions). I’m also not fond of the ROG Ally controls, especially the dpad. So, I might just be weird and my opinions, on ergonomics and controls at least, could be very far from the norm.
My favorite retro dpad is on my 8BitDo SN30 Pro 2. It’s just perfect. I think the Odin Base is also fairly amazing and I’d put it at my #2. Our RP2+ underdog would be next, followed by the Miyoo Mini Plus of all things! The variability of those devices is huge though, so it is possible I just got a few “far above average” dpads on those MMPs (I also got some bad ones that I had to return).
My Anbernics I could probably group together and would put them next (they are fine). Then there would be the unfortunate outliers like the G Cloud (my favorite device but I hate the dpad and buttons), the RP3+ (almost as good as the RP2+, but gave it away), the Flip (I have the Sports Red, and my dpad sticks to the paint, so pretty bad), and some older more vintage emulators (my arcade gamer dpad is so bad that I had to cut pieces off of it just to be able to use it!).