When choosing an alternate it draws a direct to it. Is there a way to plan the alternate properly. There’s obviously too many variable as to how and when one would choose to route to an alternate. However if you’ve rubber-banded the route from your destination to alternate in advance it gives you much less work figuring out things like heights, times and NOTAMs / restricted airspace. (And not ignoring pointless notams/warnings because you’d never fly the direct route.

A diversion is a busy time so having some of the route plotted will give you an easy way of “intercepting” your diversion route, knowing you only need to worry about the bit between where you are and the diversion route