After seeing some of your vids I saw a mistake regarding your problems with spartan charge.
From your perspective. You are in a firefight get hurt and hide to recharge shields. Suddenly get spartan charged.
In halo 5 you need escape possibility when hiding to charge up your shield. Since your position is given away its easy for someone to run in and charge you fast. Instead of hiding in locked corners its better to hide right next to a box or ledge you can climb on or next to a doorway to run around in both directions.
You can also run away while low shields if there's no teammates to help. You can trick people by going behind something, and if they go around on the other side, you can turn 180 degrees and run the other way, jump trough a window, hide and heal.
Your playstyle reminds me more of halo 3 and you should definitely try more quick moves, as it's very helpful. Then spartan charge won't bother you as much.
Having played around with running around, jumping, clambering and boosting its the most helpful part of getting good at halo 5, when you already got the shooting skills. Sometimes people won't even notice you if you run past them.
So I think a main problem is all of us classic players aren't really trying to master new mechanics. When I first started playing halo a long time ago and tried to become better, me and a friend went in custom games and tried out spots on the maps and explored kill distances, how many shots, and a lot of different stuff.
Getting older the explorer slowly dissapears and gets replaced with the settler. I took some time to adapt to dodging spartan charges. Not that I'm perfect at that, but I found some ways to deal with it, like a plasma grenade ready at hand for a good trade.