Most private pilots who have a night rating do not use it and the same is true of the IMC.
I can see where you are coming from, but have to say that while night flight is perhaps always avoidable, an IMC Rating can be extremely useful, and indeed it is very difficult to do flights of any length in the UK without it. It also gives you VMC on top privileges outside the UK (anywhere this is permitted under VFR) and that is very useful for flying into Europe.
For aerobatics, none of this is relevant.
While one can always be accused of pushing a novice into something he/she is not sure about, one can also argue for doing things as early as possible so as to keep as many options open as possible. Getting the colour vision thing sorted early on keeps all the options open for later.