Most do share strife specibi except for the Megidos. Aradia used whipkind but Damara used two wands. 

In case the session needs to be scratched. The scratch construct is located on the Time player’s planet. 

Aranea and Vriska’s mind control powers work on impressionable trolls or trolls with low self esteem, not just trolls lower than them on the hemospectrum. Aranea has had billions of sweeps to hone her abilities so it’s no surprise she was able to control Gamzee.

The Beta kid’s session does have Time and Space players: Dave and Jade. 

Whether or not a session requires a knight class hero hasn’t been stated in-comic. Time and Space players however are required for a session.

Here.

His grandmother, post scratch Jade, knew the Condesce was working for Lord English and that she was afraid of him so Jake’s grandma changed her and Jake’s last name to English as a big “fuck you” to the Condesce. 

Here. 

The Alternian sun is referred to as blistering here and only a few trolls can withstand it. 

From Andrew Hussie’s formspring.