FYI: Don't feel bad at all about having to use your phone to film your hunts, as most smart phones nowadays shoot broadcast quality video. The ONLY reason I don't use my phone to film is, I like being hands free, as digging, holding a camera, etc. is cumbersome, to say the least.
Updown is correct, there is a plethora of free video editing software out there, which suits all experience levels, and can be used on a variety of devices (smart phones, tablets & desktops).
As for advice, I should be the LAST person doling that out, as my videos aren't exactly Scorsese-like masterpieces, lol.
As a general rule, I've found that shorter videos are better, as it's easier to hold someone's attention for 3 to 5 minutes, versus 8, 10 or longer. Unless one is digging up some incredible items, it's tough to expect someone to watch a longer video in its entirety. That's why most of my videos are around the 5 minute mark, if at all possible. Does anyone really want to sit through a 12 minute production of me digging mercury dimes and wheat pennies?
As for splashy graphics, music, and all that other puffery, it's mainly a gimmick, which some people enjoy, but it's the content that's king. Splice your finds together, and cut out all extraneous footage that takes away from the live dig...it's not necessary.
It's not rocket science, just takes some practice. After a while, you'll develop a signature style, which will show though in your videos. It might be the editing, pacing, etc., up to you.
To be honest, I think your stuff is great already, and will get even better as time marches on. Most importantly, get out there and find good shit, as without that, it won't matter what video camera or editing program you use
Joe