[eridius]

I use tmux over mosh on my Linode. I've just never found it to be particularly useful on my local machine. Especially because it removes the ability for my terminal to manage history and requires using a keyboard shortcut in order to scroll backwards in history.

[phaemon]

I believe Terminal.app handles mouse events differently, so the standard tmux config doesn't work right. Maybe see if https://bitheap.org/mouseterm/ improves matters for you.

[eridius]

Terminal.app doesn't handle mouse events at all. I filed a radar for that a while ago. But I don't consider that good enough reason to use iTerm2 as the programs that actually support CLI mouse events are very rare.