Rear Suspension Uptravel only 2.75"?

I did some work last week to upgrade my rear icon RXTs to option 3 and installed a ubolt flip kit with wheelers superbumps. If the stock hub to fender measurements for a TRDOR are to be believed (22" in the rear), I'm looking at +2.5" passenger and +2.25" driver. This makes sense when you consider normal taco lean in addition to a dual ARB air compressor and 7 gal aquatainer in the bed on the driver side.

But what doesn't make sense is the bumpstop travel. I'm looking at doing shocks next so I just took some measurements and it's only about 2.75" on each side. Is this typical? I know the superbumps sit on a little platform but it feels like I'm sacrificing a lot of uptravel vs stock.

Are there other options that might bolt into the wheelers ubolt plate that are more low profile?