Give separate circuits by the same conduit. You can do it, make sure the conduit is large enough to hold the wires easily. The main drawback here is that, although you don't need another conduit, you also ask to run three circuits at home.

Feed separate circuits through the same conduit. You can do this, just make sure that your conduit is large enough to hold the cables easily. The main disadvantage here is that although it only requires another conduit execution, it also requires the home to run three circuits at your home.Keep them in a circuit.

When I run 4 circuits in a channel (single phase, 8 current conductors). The 70 de-rating table, which makes 21A, which is sufficiently good for 20A switch.

If individual ground cables were required, they would be 3 circuits of 20 or 15 amps, but with a single ground or duct cable like EGC you can get 4 circuits there.

for a circuit of 15 amperes allowed for 10 outputs and for a circuit of 20 amperes 13 otlets allowed.