I'm using ETH as my "core" holding, as I find it overall a better coin, the recent double up in value from the low of 330$ or so shows how important it is in my opinion! NEO has been a good core hold for me as well (as well as a good swing trade one). OMG seems to be one of the most stablecoins compared to gwei/sats and I read about some people who use it as a "stable currency", which kinda would make sense.
However my portfolio is 99% altcoins during HODL sessions as I prefer to have more chances at making more money from lower marketcap coins