I don't disagree with you - the software on the ecoflows is not robust, especially when upgrading. I made the decision to go with an all in one for a bunch of reasons, most of which are still valid. It was simple, it did not require specialty knowledge, and it wasn't really more expensive (at the time).
If I were re-doing the electrical (and I might), I would probably go with individual components. That would get me some redundancy, and make the system repairable. Though today if something goes wrong, it's very simple for me to unplug and verify that it's the power station and not the rest of the system. Then if it is the power station, I can take it to costco, get a refund, and order a new one - new warranty, new batteries, and each time I've done this the price has gone down. In fact I took the $500 I got back last time and invested it into this battery - getting me more than 2x capacity, and redundancy.