The best zoom available for these is the 20-60 MC II eyepiece
and it is better all around than the 20x45. Twist up eyecup,
wider FOV and brighter coatings.
If you are wanting a fixed eyepiece, lots to choose from, and
24x may be a good all around size. These eyepieces are getting
hard to find, so go back on the subforum, and find out what
others are saying about the size to get.
Myself, I like the zoom, when light is dim I can back things off
and get along well, and then I like the power when I need it.
The 20-60 will give you that.
Jerry