Background
I've been playing LoL for a short while. I started with blindly following guides and slowly moved towards adapting my items and abilities to the situation. I still haven't experimented with runes and I don't know if I actually should, at least not at this point. I just watched a 3-hours long guide explaining all the runes and their uses and it really got my imagination running. There are so many rune builds I'd want to try with so many champions now that I understand what they do!
When I play, I want to have fun more than anything and I really like the satisfaction of making something unorthodox work. At the same time I don't want to be the reason why my team lost. It's fun to go 1-7 with a troll Magic: the Gathering deck, because winning against the all odds matters more to me than actually succeeding. But in a team game like LoL, winning consistently should be something I'm at least trying to do.
Problem
However when I check stats on mobafire or mobalitics, it seems that best runes for every champion have been already solved. Top 3 builds with highest win rate usually have very little difference between them. Different guides show very different rune build, but successful Bard always take specific Resolve/Domination runes and every successful Garen will take Precision/Resolve with only variation being which resolve rune should be taken, etc.
I understand that most of those runes were most likely discovered by experimentation and that, although unlikely, there might be an undiscovered set of runes that is even better than what is currently at the top. But I still don't know enough about this game to understand why I won or lost. Did I play really well, did my opponent play well, did my team make macro mistakes, did I or someone else buy wrong items or did I pick the wrong rune? I notice my skill shots getting better and abilities making more impact on the game as I get more experience with a champion but other than this simple feedback, I don't think I could tell a difference between being behind because of bad runes and being behind because of any other reason. And if the best runes are already known, I feel most of the times I'd just be making my champion weaker and hurt my team by diverting from them.
Question
Keeping all the above in mind, how much would I be hurting my team by choosing suboptimal runes I feel might work with a champion instead of those recommended by meta trackers? Is there any value in experimenting with runes and trying to adapt them to my play style or should I adopt my playstyle to the runes that are currently the best?