Here's my two cents -
I've been in the same boat for years. My solution:
1) Disk space - the amount of effort that goes into your videos combined with having a rare perspective few ever have on this forum tends to make be believe that deleting video because of little disk space is like the tail wagging the dog. I just saw that Costco now sells an 8TB external hard drive. The cost is prohibitively high, but the good news is that every time they come out with a higher capacity drive, the ones with less capacity drop in price. I've seen 4TB external drives on sale at Costco for under $100.
I have several external drives and one 4TB, which I think of as the "mother ship". I use Goodsync (best sync program), which automatically allows me to quickly back up my desktop and laptops using a 3.0 USB.
Point is -- use, the hardware is an investment, but if you're spending thousands of hours traveling and shooting video, the high capacity external HD to archive all raw footage is a smart investment.
2) Video editing - Again, good video editors are expensive, not free, but in the long run worth their weight in gold -- particularly since you spend so much time with your filming. I use AVS Video Editor, which preserves the resolution and quality of the original, and allows you to edit out footage easily. It's very user friendly requiring no real editing skills. Within one edit, you can merge videos from different formats then save the end product in any format you want, inclusive of whatever resolution quality you desire.
Because I got screwed purchasing this software in the past when I got a new computer, I said fuck it, and went to Piratebay to get a free copy of the updated AVS. Yep, I'm a bad boy, but everyone on this forum have had an opportunity to download my beach vids, which were created with AVS.
If you PM me, I can make it easy for you...