The first trip, and the next 3, were all at Royal Pacific, and we LOVE it there! Great theming, extremely compact, awesome pool (but no slide), real sand in part of the patio, 7-10 minutes walk to CityWalk, or the water taxi is RIGHT THERE. Those trips were Thanksgiving 2015, May 2016, Thanksgiving 2016, and October 2017.
The most recent trip, we wanted to splurge a bit, so we checked out Portofino. Also LOVED it there! Slightly more upscale feeling, absolutely charming theming, much larger, more sprawly, but also more ... authentic feeling? I don't know, I just loved that we walked up some stairs, down some stairs, through a gallery, and across a courtyard to get to our room. It really felt like we were in Italy. And the pool! It's an aqueduct ruin. Totally awesome, has a slide, but a bit small. And most was pretty shallow. It was perfect for November, but it would be pretty crowded in July.
From all I've read, any of the 3 deluxe Uni hotels is a fantastic experience. We had gravitated to Royal Pacific due to consistently lower cost, but it's still a "deluxe" experience, and even after Portofino, I would stay at RPR again in a heartbeat.
Each of our Uni trips has been 2.5 to 3 park days, with 2-4 hotel nights (depending on flights and family / travel). We have family in FL, so we've taken to splitting the Thanksgiving holiday between the relatives and the wizards. That way, we can count on getting a minimum of 2 trips out of our annual (or "seasonal") passes. Plus, the annual passes usually allow a room discount too. We've found them to be a great deal.
We don't combine Disney with Uni trips. Honestly, each place has it's own bubble. We don't like to pop the bubble, either one!
Edited to add:
If you're planning a Uni trip, there is a Universal subform on DISboards. Not super active, but there are some very helpful & friendly folks over there. The stickies are fantastic resources for hotel info, restaurant help, and literally, everything Harry Potter.