You can group the logins on the MQ2 task tray icon. profiles -> create new -> profile set (use same name for all toons) Then put checks on all the toons from the profile you want to load and use the "load all" option.
I think mq2autologin can also be setup to load certain sets of toons.
Yeah not sure how much you can improve that - moving your install dir to a SSD generally helps
For setup, you can auto launch a macro on character load in autoexec.cfg or server_charname.cfg if you need specific ones. I have a /mac launcher to claim any dbg rewards that Knightly wrote in mine. You could auto start kiss, tell everyone to cast origin or drunkard's stein to group up everyone etc.
Using MQ2autogroup is a huge help as well