2. A battery pack under it in the front like https://smile.amazon.com//dp/B018VK1TAU
hopefully it's thinner than the legs of the keyboard.
3. A capable tablet
4. A leather holder/folder which a) holds 1 and 2 in one half b) the tablet in the upper half c) has adequately long two pieces of string on each side connecting the corners and thus holding the tablet upright when open. The battery pack is the counterweight to the tablet. If you add nice wide head studs standing out a little on the sides then you can feed the string under the heads shortening the string and thus changing the angle of the tablet.
Would anyone be interested in this...?