Don't use tmux. Use a nice wrapper for tmux instead (e.g. like byobu).
Otherwise complaining about tmux and talking about hacky workaround alternatives is a bit like complaining about the internet and advocating for the telegraph as a hacky alternative because you don't like writing your own HTTP requests by hand and morse code is so much simpler.
Having said that, if really all you want is pane splits / window management, lots of terminals have their own solutions for this. Guake is a good one.
disclaimer: I use Guake and still prefer to just use tmux (byobu) from Guake
Yes to all, with caveats, since Guake is a GUI terminal, not a multiplexer.
Sessions yes, but not in the ssh / surviving-restart sense. But within the same login, yes, because it's a drop-down terminal which stays open in the background at all times even when exited, and thus running jobs don't get killed when you exit. And you can have multiple windows, and split-panes within windows. These are obviously remembered when toggling the terminal on/off.
Startup layout and specific (remembered) configurations etc can be configured via hooks at start / show events. Guake events (e.g. splitting / toggling) can be triggerred externally / programmatically via normal cli commands, so you could either add hooks, or bind keys / commands to performing batch actions (such as loading a preferred window layout with specific programs etc).
Otherwise complaining about tmux and talking about hacky workaround alternatives is a bit like complaining about the internet and advocating for the telegraph as a hacky alternative because you don't like writing your own HTTP requests by hand and morse code is so much simpler.
Having said that, if really all you want is pane splits / window management, lots of terminals have their own solutions for this. Guake is a good one.
disclaimer: I use Guake and still prefer to just use tmux (byobu) from Guake