For what it's worth, I agree with your first and last points. I respect that Chelsea isn't a hot mess like her co-stars, but that's not saying much. In the grand scheme of things, she's essentially just a functional adult, which IMO is nice but doesn't make her such a saint that she's immune from snark. I just find her annoying to be honest (and not just because of the voice). Obviously that's my personal opinion and not some great character flaw of hers, but regardless it sure meant I did a lot of fast forwarding this week. She was particularly grating for some reason.
As to your last point, I wouldn't go as far as to compare her to Leah, but I could see Aubree being a handful as a teenager. She's adorable, but she has a defiant streak that Chelsea doesn't seem to be great at handling. Also throw in her potential daddy issues, and things could get rough. Sadly, I guess a lot of the sweet little ones on these shows are destined to repeat their parents' mistakes.