If you can stretch, then this Surface Pro 4is an incredible deal. Includes the keyboard, and there’s a trackpad on it.
I’d have suggested the Surface 3 (non-pro) but that’s not on sale.
I wasn’t aware that can do all of those things on an ipad?
Pretty sure you can edit Office documents on iPads and Android. However you get a cut-down version of Office, wheras that Surface is a tremendous deal.
Those Linx Windows tablets are also decent for the very low price, apparently. Also run full Office.
Incidentally, why did you specify tablet in the first place?