Thanks for the video, it was helpful, but I am still slow to react to the cases
That's why you need a good lookahead ;-)
You don't need to have a full plan of all your pieces at that level but less searching for the next pair helps a lot on this level.
I'm also around 30 seconds to recognize pieces earlier and plan the cross were the points that helped me to get sub 30.
I would also recommend to learn full PLL. For the G-Perms its maybe easier to forget the pictures with the changing pieces and just look on the Headlights and the Block.
Put the Headlights always to the left. There is a set of algs that is fully mirrored, so you basically have to remember just one alg
Ga (block down) -> (R'2 U R' U R' ) (U' R U' R2) (D U' R') (U R D') <- Gd (block right down)
Gc (block up) -> (R2 U' R U' R ) (U R' U R'2) (D' U R) (U' R' D) <- Gb (block right up)
For Ga, Gc you can read the alg from left to right, for Gb, Gd, read it right to left.
Ga and Gc Start to the direction of the side block and if the R Layer turns clockwise, the U Layer turns counterclockwise, then you change directions but keep the same rule. If you change to the third block you keep the direction of th U layer but change the R Layer.
In the backwards direction you start to turn from the block to the gap and turn U and R layer to the same direction first
Maybe a little hard to explain but with this method I could learn the GPerms quite fast and because of the easy rules i could still remember them when I learned OneHanded.
If you do a Ga you get the Gc, so you can learn them together and just reverse the alg to get back.