Regarding the gears, you need to inspect the leading and trailing edge of the gears where they mesh, known as "dogs."
These are the dogs, you just want to look at the engagement side on the drive gear and the receiving side on the driven gear. Once you spend some time figuring how the transmission works (moving stuff side to side and front and back), it's easy to determine where the wear should be. The concern is when the edges are worn or rounded at the interface. The wear will be on the leading edge. If you are not having problems you won't see any issues.
Here's a bad one-
Here's a heavily undercut gear to prevent slipping-
Spend some time searching for "undercut gears" and you will find good info regarding inspecting your gears. You do need to separate the gears from the shaft for a full inspection, but a cursory glance should let you know how deep to go.
If I dig around a bit I might find my worn gears to give you a reasonable view of what I have seen. Otherwise, if you don't have any trans problems, you should be good as you are.