You seem to have a reasonable starting force.
And I see 2 rough options for you, one more kabalite focussed with a squad of wyches and the other slightly more cult with a squad of warriors. Later on it will be important to get some more command points but for 500 points and just learning the game I would worry less about that.
Kabalites with some wyches:
Archon (with huskblade/ pistol)
2*5 warriors (w blaster)
succubus (w glaive and maybe pistol instead of a wych #6
6 wyches (w power sword and wych weapon)
This should get you to 500 ad in some phantom grenade launcher to get to 500.
Archon (with huskblade)
5 warriors (w blaster)
succubus (w glaive)
2*5 wyches (w power sword and wych weapon)
This would leave your HQ to run, as well as being slightly low on anti tank, you do still have enough points to either get a blaster (for the reavers) or 2 blast pistols (1 for each HQ)
When expanding your army in both cases it might be good to get some more anti tank/heavy infantry with a ravager, as then battles also become larger and you are more likely to meet tanks.