The main shortcomings I think about are towing and highway driving. But my Jeep experience has been a 1948 Willys, a 2003 2-door 4-cylinder Wrangler, and a 2006 Liberty CRD. I haven't tried the Willys on the road for obvious reasons. And the only Jeep I tried to pull the boat with was the Liberty. It went fine on the road, but backing into the boat ramp I was sliding uncomfortably even in 4WD, so I swapped the trailer to another vehicle when we finished on the water.
I'm sure the Gladiator is a great highway improvement over the 2003 Wrangler (if for no other reason than wheelbase) and I would hope it behaves better on the boat ramp than the Liberty. Your thread keeps inspiring me to want to give one a try. They should have given you more than 15% off MSRP for that.
I'm not sure what you're driving now, and I haven't driven a Liberty. But I have driven previous generation Jeeps from Cherokees to Wrangler Unlimiteds, and some others in there. No doubt, the current generation (both my Gladiator and also Wrangler Unlimiteds I've driven) are much, much better highway vehicles than the older ones.
The "comfortable" highway speed (above which it starts buffeting around more) I find to be in the 70-75 range. I generally don't drive it above 70. It can go faster, and some of it depends on how much tolerance you have for that. So if you drive long highway stints at 85 today comfortably like you can do with most modern pickups, this might not be the best choice.
Towing, I have no idea as I haven't towed with it. I'm not sure whether your preference is the manual or automatic, or how big your boat is. Our boat that we used to have was a 23' cuddy cabin boat which
@jesse now owns. I would definitely not want to tow that with the Gladiator. I hated towing it with the Avalanche, which was a bigger/heavier vehicle.
(ref: "Thinking About a Boat", the first "Thinking About..." thread:
https://www.pilotsofamerica.com/community/threads/thinking-about-a-boat.73964/)
If your boat is smaller, then I don't see an issue with that.
I did recently pull some bushes out of the ground using the Jeep. The Mojave doesn't have the 4:1 low range of the Rubicon, it's got something like a 2.72:1. Even with it in low range and whatever reverse gear is, it was hard on the clutch. The lack of a proper granny gear in 1st and fairly tall ratios isn't ideal, but I think the 8-speed auto handles that better.