2- Sell a big part of my coins to buy more at cheaper price later.
3- Unload all my bags on the market.
4- I will just rebalance my portfolio. Nothing more, nothing less.
5- Sell some of them to buy something else.
You won't know or determined what will be the new ATH. If the price able to passed its previous ATH, you will expect that the price will increase more so all these lists you have made will be all disregard since your mindset is focused on the increase.
What you need to do is to put a price target. Whatever the price situation, even the bull run is strong, execute without hesitation. That's a better approach compare expecting for more as it might lead you to regrets.