It would be good if I can select multiple weapons or armors of same type and sell them with one click in Armed Surplus regardless of their quality. It's really annoying to sell them one after another with multiple clicks.

Same goes with inventory if I wanna throw them away. Let us have an option to select multiple items at the same time and throw them with one click. 

I hope my point is highlighted.

Check this post done by Baccy, should give you exactly what you need;

[Script] NPC Quick Sell w/ Item and Quality Filters

If on mobile, you can use firefox and violentmonkey extention for the scripts.

I fish for high/low % weapons most days and the quickest way to sell stuff that I've found is clicking in the press, typing 1 and then pressing Tab twice to get to the next box.