So, once again I'm here asking your assistance (must be 3rd time in a week

)
I'll just get straigth to the point. I'm going to play against chaos within 2 weeks. He will have 1000p + 200p of fortification and I will assault with my 1250 points.
We will only have one objective that the defender defends. Besides those we will count killpoints without warlord, linebreaker or first blood. Simple, and we both like it that way.
So this monday it was my turn to defend and even tough in the beginning it seemed that I would win, he won the game 5-4. (I believe his main thing was that he had 3 sorcerers in his army.)
And I was planning a list like this for my assault:
HQ
Librarian - 100p
Elites
Sternguard - 205p
PF, 4x combi-melta,
DP
Sanguinary Priest - 65p
Power Sword, will join the Sternguard
Troops
Tactical Squad - 180p
w/
ML and meltagun
Tactical Squad - 180p
w/
ML and meltagun
Heavy Support
Dev Squad - 145p
w/ 2x Plasma Cannon & Lascannon
Predator - 100p
Autocannon &
HB-sponsons
(Still have 275p left)
Here's some questions:
1) Librarian with Sternguard or Tacticals? Terminator armour/Epistolary uprgade worth it?
2) Should I take more Priests? To join Tacticals.
3) Should I buy
TLLC for Predator?
4) I was thinking to change one of those
Tac Squads to something more
CC-orientated. Either Assault squad or two, or
DC with Chaplain.
5) Transports for Tacticals?
6) Should I take more
FA? Bikes or Land Speeders for example.
Criticism expected and appreciated.
So here is the list he had (said he'll only make few changes):
2x Sorcerers,
lvl 1 & 2
9x Thousand sons
20x Cultists
5x Chosen ones
5x Havocs w/ multi-meltas
Hellbrute
Defiler