Hi andrius1,
These are two very good points, here is my take on both of them:
1.- New additions.
My strategy focuses a lot on high and mid-caps, since the volatility of these kind of projects is usually lower than low cap coins. For good projects that may end up in the portfolio, or rotating some of the projects included in it, i am of course all about it.
I have had some percentage rotations in the past due to different speeds in the projects and the expectations in them, so these are things I have under consideration, but I do not want to be trading very often, since this is a long term portfolio. An addition is done looking years into the future, and I am happy with having certain percentage of a coin in my portfolio for the long term, which takes us to point 2.
2.- Selling outperformers, buying underperformers.
This is a balancing strategy, and a way of realizing profits in a certain coin. One of the things I value most about the portfolio is the diversification, and the way of having a steady diversification over time is keeping percentages as planned.
As a way of rotating overrepresented coins in my portfolio, I choose selling after a significant increase in price, as it is a way of locking profits and at the same time averaging down (if possible) for another coin I have in the portfolio. I will complement this strategy in the future by having some part of the portfolio as "Free USD", in case there is no obvious rotation in case I want to lock in some gains.
I hope this clarifies a bit my thoughts and strategy, I may be 100% wrong, but it makes sense to me to try and reduce some volatility and keep things simple in this crazy market.