"Dock two vessels on or around" contracts should be replaced with a "Dock two vessels in space" contract
Out of all the explore contracts, this one's the worst. NASA didn't go "okay, we docked in LEO, but what about Moon orbit?" and send a test vehicle out there, but that's what the game expects us to do because there's this idea docking is actually different around the Mun.
This breaks the flow of exploration with a sudden "okay, you've landed on the Mun, you've docked in Kerbin orbit...but have you docked in Mun orbit???". That alone would be bad, but on top of that, it requires separately-launched vessels, which means an Apollo recreation doesn't satisfy the contract, which is completely something a player wouldn't expect (and I know I didn't my first time trying to satisfy this kind of contract).
As a final nail in the coffin, the one version of it that doesn't make me want to pull my hair out is the one for Kerbin...because it can be satisfied with some simple rovers sent to the side of the runway. It really doesn't feel like exploration when I just need to hitch two cars together. Moreover...why would docking two rovers on the surface of the Mun be comparable to docking in orbit? It's docking in space that's the difficult one.
I suggest that this kind of explore contract be replaced with a special one similar to the "Escape the Atmosphere" and "Orbit Kerbin" contracts. This special contract would ask you to dock anywhere in space (orbit, flyby, or suborbital around any body), so that it's one and done. It should also explicitly say you need to launch the vessels separately.