1/ The item has more than 10+, so that will problem for function properly as how player can type 10 or 11th item? That led reason why press 2 and press 1-6 for switch any pokemon, but press 3 and then you need click to item (cannot press number)
2/ Sound good
3/ Mm, I think you should click rather than press number. Press number can make many mistake, and you know what problem when you click wrong number. In fact, click yes no is less risk, but people still have mistake. So it should keep as click Yes/No rather than click by number...
4/ No idea