I totally agree with you about the centralization of ETH and decentralization of BTC. BTC still rules in my play book and nothing else comes close yet. ETH has a lot to prove to convince me it can be a real player in crypto.
Actually, I am beginning to think about ETH a little bit like some kind of potential quasi-centralized system that can be built upon BTC (at some point), that is if it can last long enough and not get dumped into oblivion... At the same time, there is a lot of misleading information that premise the various ETH pump attempts including suggestions that it is Bitcoin 2.0 and that bitcoin is broken... blah blah blah, whatever.
And, actually, I am no bitcoin monogamist because if at any point in time, it seems better to move over to another coin because of better decentralization and immutability fundamentals, then I will do that. There is no alt coin that is even close to bitcoin in regards to decentralization and immutability fundamentals.
But, yeah, if you merely recognize pump opportunities with ETH and don't get caught up in the bullshit, then there is no problem to take some risk with some of your crypto money or whatever categories of money you want to conceptualize as being within your risk tolerance to put into it.
As I mentioned earlier. Other coins are simply a means for myself to accumulate more BTC at this time. No other coin has shown the resiliance Bitcoin has. It may take another 3 to 5 years to see another coin prove itself as legitimate (useful).