Welcome from Texas!
I've hunted from my saddle using a bow, crossbow, and rifle. I've even used it for photography to get pictures of animals out in the wild. Use it however you want!
There's a ton of different options out there, as MattMan81 mentioned. There's a bunch more mechanical devices too (F4, Trango Vergo, etc). Unfortunately you won't find out what you like or don't like without trying them yourself. A good recommendation by boyne bowhunter is to find a meetup near where you live and go there. You should find a bunch of different things there that people will let you try, to fit just about any budget. You should probably consider that as well. If you have a $150 total budget, a figure-8 or munter with some prusiks with a rappel rope and a DIY stick will probably be what you start with and possibly add/change more later. Bigger budget will let you get into some mechanical ascenders (Madrock et al) or a fancy one-stick.
As far as backing up devices and why you don't see some people on videos using them - it's all risk assessment and management. How much risk are you willing to accept - and that's only a question you can answer for yourself. Do your research on any methods you choose, and see what failure areas each component has. In my opinion it's a lot easier to free-fall down using a figure-8 (traditionally tied, not locked) than a Madrock so I never understood why some will back up a Madrock but not a figure-8. But I could corner-case scenario any choice and risks until we die of old age