- the docking adapter discussed in the answer did not make it. However, the answer offers a couple of alternatives, so +1.
- they painted some crosses on the JWST to make alignment easier.
- JWST's L2 location is really far from Earth. It's about 4X the distance from the moon. So a manned mission is currently infeasible. But maybe in the future.
- while fueling may be possible, any other sort of maintenance probably isn't. To save weight, the JWST is mostly glued together, unlike Hubble which used spacesuit accessible bolts.