The problem with short term strategies is
at some point, bitcoin is going to make a parabolic move to its next ATH
and then, at some point all the alt coins are going to make a parabolic move too.
So, the most important thing is being in those coins when they make their move. As such, getting out of those coins, even for much gains during a week is very hard for me.
The question is your timescale. Here I present analysis for weekly investments. If we go up I expect there to be enough time to get back in and it does not matter if I miss a few weeks.
But when you invest on monthly scales or larger, then it is a very different story. I actually did an analysis for 2 month investment and that was 80% bitcoin, 20% cash and no ethereum at all.
But most important is to have good risk control. Bitcoin can go up 30% or down 30% in a week. If any of that is a disaster for you then you have too much risk.