We've stayed at Lathrop several times due to it's proximity to us for a quick weekend camping trip. There's plenty of trees, which is uncommon this side of the mountains, and a couple of lakes which provide good fishing, water sports and a swim beach. The hosts and staff are very welcoming. As with most Colorado State Parks, there is electric on site with sporadic water points (*usually* if you have 150' of hose you can fill your fresh water from your spot) and a dump station. Most spots are pull through with a few exceptions and very spacious so you're not bumper to bumper with your neighbor. Firepits and picnic tables are included as well. Showers are $0.50 for 4 minutes - not too bad.
Nestled between steep cliffs next to the Colorado River the views of this park will take your breath away. This park has mostly pull-throughs (from what I can tell) and plenty of space - RVs are not on top of each other. There are several ponds which are well stocked for great fishing. The Colorado River runs adjacent to the park as well, but we didn't fish it. We enjoy watching 2 bald eagles diving for lunch in the ponds, it was amazing!
A couple cons but nothing that got to us too much: this park is just off of I70 so depending on where your spot is you may encounter some highway noise. The railroad is also on the other side of the river, so very occasionally you'll hear sounds of a train going by. All in all, not too bad.
Plenty of trees, plenty of water and beautiful views, we'll definitely go back.