Some levels do not require user intervention after you have pressed the Start button, all preparations can be done before starting. Or vice versa, before the active start of tactical movements, you need to wait some time (until it rains or the grass ripens). It might make sense to add a fast forward button. Maybe onscreen near timeline, maybe bind it to keyboard - when you pressed it time moves faster, when released moves normal. I don't know is it still needed in later levels (game still to hard for me, but i'm trying!), but as for earlier - it is have some sense.