Don't think I count as high-profile (56k followers on Twitter), and I largely post the same content both here and on Twitter, G+, Tumblr, and FB. I also tell people about all platforms I'm on, in case I'm what keeps people on Twitter when another platform, like Mastodon, would suit then better.
I definitely intend to stick around, and don't miss any features (I like the G+ circles, but don't have any use for them on this account).
People are generally nicer here, too. :-)
Only one person writing and posting. Only my Tumblr is automated, through IFTTT. I add more tags here and on G+, for instance, and a story that takes two tweets might get me in one toot; I try to follow local custom. :-)
I read replies and comments everywhere, and try to answer when I have something to say. I'm also dipping in reading, but have limited time, alas. (Still trying to get used to your new avatar.)
@veer66 @Gargron I find that Facebook (which is curated by algorithm, so is hard to get visibility on without paying) and Tumblr (which has a culture of commenting via reblogs adding comments in hashtags, which are only visible if you seek out that reblog) are the worst for comments.
Google+ is small in terms of active users (as opposed to gmail/youtube users pulled in), but they tend to be quite engaged.
I might be lucky, but I see around 5-10% of my followers on G+ engage in some way (+1, share, or comment) on most of my posts, which is probably an order of magnitude greater than anywhere else. This might be because my following there is so small, and only consists of really dedicated fans.