I fully agree about the signup process, we were actually in talks a few months ago about providing different options for that to allow users to jump in and use hive instantly while figuring out keys and an immutable account later, unfortunately it got stuck somewhere but I don't think it's something too difficult or expensive to create so will have to try and move it forward if no one else is going to.
About the latter thing you mentioned, I think stake distribution is going to help there more as well, possibly with front-ends having smarter recommendations than having to rely on curation projects to both recommend you new users and make sure to curate them.
I feel like if an additional easy option exists it will be something like Binance...They own all our keys and we don't have to worry unless Binance gets hacked. That could be the account for the grannies on Hive so they can jump right in.