[Closed] Which software for merging and cleaning up GPX files?

I've got a collection of about 10 GPX files from a local area from hiking up and down various trails and exploring off-shoots.

I want to be able to snip the tracks into individual sections, remove the uphill sections (or reverse some of them) and remove the any spurious sections, then stitch sections back together.
The time stamps aren't important as I just want to use the final result for navigation purposes.

Best software I can find so far is Topofusion though it's a bit clunky.

Any other suggestions? (I don't mind paying a small amount) but not sure whether Komoot or RideWithGPS are any good at cleaning up GPX files....