I think so many tyre threads get started that people get tyre fatigue 😉
On super smooth, hard trails then very low profile knobbles like the Aspen are good.
On softer trails then something with more knobbles is good, like the Ardent or Advantage for example. The softer and muddier, the bigger the knobbles.
On loose, dry trails or gravelly trails more knobbles is good again, but you could also give a 'micro-knobbly' tyre like the Kenda Small Block 8 or Maxxis Larsen a go.
To be honest an Aspen rear and Ardent front sounds like a pretty sound summer tyre choice and should cope well.