Photoshop Mobile: Not enough keyboard shortcuts for painter

I’m an artist so I use many keyboard shortcuts for painting. But Ps for Ipad Pro does not have enough. For example:- Holding shift for moving straight.- Cmd for picking color while using Brush.- Cmd+del & Ctrl+del DO NOT work to fill color.- Cmd for minus selected area while using Lasso tool....I feel very uncomfortable to move hand from keyboard to screen to use the touch circle so often. I have a keyboard with 2 shift & 2 cmd keys, but am FORCED to use that touch circle. Why??!!!!!!