I you want a gopro, it doesn't have too much extra cost. The software is free; the cost is in mounts and cases. I, personally, have spent quite a lot; but for skiing, real steel shooting, airsoft, diving, and such. For airsoft I have a GoPro Blackout case (£45, need it as te red light paints a target on my head in The Mall), a aluminium RIS mount (2 for £20), a few extra mounts and pieces (basically comes with the camera), and that's it. Filming airsoft in woodland isnt ideal; you can't get good footage. At somewhere like UCAP Sandpit, the open spaces Han give some good video; check out LunchboxTV for an example. CQB gets good footage, as long as it's not too dark, like basement areas of The Mall. You can look at my YouTube thread for gameplay at The Mall.
I film very similarly to you; not to publish, just for me. However, I found that I had a knack for being in the right place to film some funny moments, so that's my only video right now.