Create configurable timer, via plugin command with long list of parameters. You can do many things with it: fully customizing it, setting triggers that to activate common events as parallel events or as autorun, only single execution per trigger activation. You also can make more than one timer and put relationship between them, so when the one goes, the other goes too.
Create configurable graphic module, to display the timer. It have Mouse/Touchscreen support too, to drag around or hide/show it via the +- icon. Creating that module is done via plugin command, with overwhelming list of parameters. Fortunately, they have default value, so if you want to test it first, you do not need to input anything given that the needed files are there. For the default graphics of the module, you should thank
@JacSkulls from RPG Maker forums. He provided them for me. Thank you, Jac!
Extract timer data to variable via plugin command.
Execute timer commands using plugin command.
Create triggers, that upon time period change (second, minute, hour, part of the day, day, month, season, year) would activate common event as autorun or parallel process, depending how you set it, and the ability to turn game switch.
Script call, but via plugin command. Yes, that possible. It haves one single parameter, multi text, and it will be evaluated (like the script call text). There, you can use shorter version for some script calls, but as con, it executes on different context (not within event interpreter), some interpreter based methods will not work.