Sorry unable to help with alternatives.
I've been using Basecamp for a number of years, although it's quirky, dated design and a steep learning curve I find it an extremely useful programme for managing GPX files.
I usually use RWGPS for route planning, but Basecamp is my go to option for:
Checking Tracks before uploading
Converting Routes to Tracks
Removing redundent sections of Tracks (e.g. the bit where I went the wrong way on the recce ride)
Dividing and joining Tracks (to change start point, enter new section etc.)
Reducing Track Points
Storing Tracks for future use/re-use
Although it's not easy to use once you've got to grips with it, it does these jobs very well.
Not sure whether that's helpful to you or not?