Excellent post and welcome.
You bring up many valid concerns about ETH. Some of these concerns such as scalability are common to many of the big currencies since they cannot process a lot of transactions quickly. Of course, a number are specific to ETH only.
I have a small holding of ETH. I dont know what the long term will be for it so I am monitoring it. There are lots of things to like about ETH and lots not to. But then the same could be said about every crypto currency. There are a number of challenges for the blockchain technology in general to over come.
Upvoted and followed.
Thank you for the feedback! And yes these concerns are common to most of them.