For small tweaks to the map, I found Potlach (the flash editor) to be OK. I've made a few edits to fill in the odd missing road or mark the point where the name of a local road changed.
What exactly did you find difficult?
To add a new way (OSMese for a linear feature of some sort) abutting an existing one, click where you want the road to start, then click where it ends. Congratulations, you have a new "way"! On the left give it a type, name etc etc. If you need to split an existing linear feature into two parts, click on one of the nodes, then click on the scissors to split it, then you can apply the correct values to each sub-section.
This morning I was trying to use Potlach to extend a street around a corner and end it in a cul-de-sac. I was able to get the street to curve around, but I couldn't really figure out how to make it end in a little neat circle like all the other streets around here. And I couldn't figure out the way splitting and joining. I had lots of problems with trying to move around, and also I got "stuck" in draw mode, so I would end up with road paths that went all over the place, then I had to go back and delete them. Maybe my mind is just too used to programs like Adobe Illustrator.
I might try some more editing later -- my first few impressions of it were just that it was too hard to use.
What exactly did you find difficult?
To add a new way (OSMese for a linear feature of some sort) abutting an existing one, click where you want the road to start, then click where it ends. Congratulations, you have a new "way"! On the left give it a type, name etc etc. If you need to split an existing linear feature into two parts, click on one of the nodes, then click on the scissors to split it, then you can apply the correct values to each sub-section.