For knife sharpening The 220/1000 and 4000/8000 combo will get you straight up to a mirror polish on any edge. Do you need it? no. But get it anyway and try it out for yourself. The 8000 grit really makes my kitchen knives sing through everything. Tomatoes, meat, stale bread, it does it all very well. My pocket knives and outdoor knives usually get finished up to 8000 as well but somtimes makes cutting through clamshell type plastic tricky. Sawing through these with a serated steak knife works better.
I have a hanging leather/felt strop from handamerican. The build, price, and customer service are great. The leather side is treated with diamond paste while the felt side is treated with chromium oxide paste. This pretty much only gets used with my straight razor or a kitchen knife if i dont have time to soak a waterstone. On the straight razor its easier for me to get the best edge when it is layed flat on a table vs using it while hanging. If you are only using it for v-type edges a paddle type is probably easier to use. If you will be using it on convex edges as well, the hanging type may be more versatile.
Making one with some spare leather isnt a bad idea if you have some, but the abrasive pastes are where its at for me.