I haven't refined my gearlist to the point yet where I feel like posting it for criticism, but I just uploaded a rough draft that might help you out.
My solution to having multiple gearlists has been to create a single spreadsheet with a bunch of different columns, each for a different trip configuration. I basically have blocked in different gearlists for 1,2,3 and 4-season camping, and variations on each of those for 2 day and weeklong trips… all of these are in addition to my "basic" gearlist, which is gear for a 3-season, 3-day trip.
Check out the gearlist attached to my profile and you'll see what I mean. Again, still needs a lot of work, so please refrain from criticism of the items on the list, but feedback on the gearlist setup itself would be helpful. For me, it's the easiest way I've found to have everything in front of me at once.
I've got another, much longer list for two-person hiking with my girlfriend, that has her gear on there, too, and divvies up gear weight based on shared equipment.
I hope this helps.