An early release of the emonCMS image included Node-RED. Node-RED is a little notorious when trying to keep it up to date (though it is better now) and having somethign else on the emonCMS system can cause issues as the layout of the partitions etc is optimised to prolong the life of the SD Card. Adding things to that, can have unexpected consequences ( as you may or may not have discovered).
HA has a mass of automation options and you can build very complex relationships between things. emonCMS will never be able to compete on that front. However, emonCMS does have some specialised automation systems (like demandshaper). HA does have a fairly steep learning curve! I use HA to control my heating and more recently my hot water (4 separate temp sensors rather than a single ‘thermostat’).
Personally, I run a supervised install of HA on a Pi4-4Gb. There is an add-on to run Node-RED inside HA effectively and I use that for my main Node-RED instance. If you do go down this road, I suggest a HDD or SDD and probably the prebuilt image. In the future I will look to move HA onto an NUC as I feel that will be more reliable and robust.