"OK, this WDW veteran is going to DL this summer".... From 2010 to 2019 we went every year in either June or July. I can't tell you for a post-covid summer trip- but I can tell you what we experience for 9 years right up to that point:
1. Weekends ? Weekdays? Which are more crowded? I always though weekdays were better , but seeing some crowd calendar say weekends are better??
To our surprise, in the summer Saturday and Sunday have always been our least crowded days and Monday and Tuesday the most crowded. This is especially true if you are going in the first half of June when the weekends are blocked for passholders but they still have weekdays where they can use passes. We thought it might change in July when the passes are mostly blocked, but it mostly held true for July as well. I always figured Saturday would be the most crowded, but it never was.
2. Park Hopper ? For a 3 day trip?
Yes. Unlike at WDW, hopping takes 5 minutes or less. We started as WDW vets, and to us DL/CA are like one big park. They are only separated by a plaza about the size of a football field to walk across and you don't have to go through security again to hop between parks. That said, the park reservation system which doesn't let you hop until 1:00 p.m. which is in effect now, does create issues with hopping and caused problems with our October 2021 trip. It gives hopping less value, but in our minds it is still worth it. It is still nice to be able to go back and forth at will. My DH has a big fondness for the Karl Strauss beer truck on the pier at CA- he has been known to disappear from DL and go over there. Also sometimes if you look at the app and see the lines a lot shorter at the other, park it is nice to be able to switch parks to take advantage of the shorter lines. It is also nice to be able to hop for dining or for that snack someone wants, or to ride that ride one more time that someone wants. Hopping is so easy at DLR. Have not done Genie + yet as it wasn't in effect in October (and we won't go back without Genie + or some type of fast pass system as the October trip was our worst Disney trip so far), but we did MaxPass many times and loved it and I would buy Genie +.
3. Do crowds thin as you get closer to closing?
Not so much in the summer, until that last hour at DL when the park is open until midnight. Not like you are probably used to at WDW. Because the crowd has a large number of locals the crowd is almost always very thin in the mornings- even on days that get really busy later. That first couple of hours in the morning is usually great-- we aren't morning people, but it is worth it. At WDW, you have about 20 minutes after opening before it gets packed, at DLR it is more like 2 hours a lot of mornings. Worth getting there at 8:00 when the park opens.
4. Any spots to take someone who might need a minute or town away from the crowds.
There is a path back behind Grizzly River Run at CA. It is extremely quiet. There are hardly any people back there most days. That is where I went this last October when that awful Virtual queue was in effect and I was desperately trying to find a place with good internet speed and quite to try to get something booked for the noon drop.