Last season there was no real choice for SCT's on astro but Fastrax kourse Kings, which we all adopted to, but they are a hard compound and are now outclassed with better compounds in other patterns so doubt will be competitive, they may be good for the front of a 2WD truck.
Schuey yellow minispikes would be the first choice to try on Astro, although they do balloon on a 2WD SCT with decent power (belting tape may cure this?)
A compound dBoots Nanobytes are awesome on carpet with much better wear rates than schuey tyres and they look like they will be as good on Astro as the spikes are a good length so well worth a go.
also dBoots have Multibytes in testing and they looked very good at Broxtowe astro track so maybe worth a little wait, not sure on their release date.
Either way i've found on a 2WD truck that you need to remove at least the outer rows of spikes/pins on any SCT tyres to avoid grip roll and allow the steering to work faster (yes i have a good servo!)
I'm holding off on outdoor tyres until season starts as there may be more choice by then.