I'm unsure if I should see Crossworlds as an 'tweaked Armored Princess' or 'Armored Princess for the Hardcore'. Which one would you recommend for a newbie?

I think that Crossworlds has a few fixes for Armoured Princess so I played that one - but being a newbie too I played it on easy and it wasn't overly difficult. You just have to choose your army with care but it is do-able if you take it slow at the start :)