1500 - Advice?

Hello Brothers.
I am new...ish to warhammer 40k. I would not say i am a complete noob, I had collected space marines for many years, and have about 2500 points worth. Although I had this army for like 7 years, I had never had never played a game. I then wanted to try something new. I decided the new grey knights were for me. Recently a games shop opened near me and I have started playing. i have played 3 games, I have won 2 games vs eldar and I played one 3 way battle against eldar and space marines. I fell just short to the space marines on victory points in the last turn. All these games were small points, 750-1250. I am trying to develop a slightly competitive list. I know that twin auto cannon dreads are the best but I don't have the money to get them or are they really worth the money? I will soon get a dread knight, which loadout and role is the best? Any advice is appreciated, and please be nice, I am still kinda new.

1500
Grand Master = 210
Psychoke Grenades, Rad Granades, Mc Nemesis Force Sword, Psybolts

Librarian = 170
Psybolt ammo, 3 psychic powers (1. Shrouding, 2. Might of Titan, 3. Varies Depending on enemy)

Strike Squad x5 = 110
4x Nemisis Force Swords, 1x psycannon

Terminators x5 = 220
Psybolt ammo, Nemesis Force Halberds

Terminators x5 = 240
Psybolt ammo, Nemesis Force Halberds, Psycannon

Paladins x5 = 290
Nemesis Force Swords & Daemon Hammer, Psybolt Ammunition

Vindacare Assassin = 145

Dreadnought = 145
Twinlinked Lascannon, Nemisis Doomfist

My Grand master will join my paladins (kill things) , librarian will accompany a squad of terminators, SS will sit on the closest objective, and vindicare and dread will target vehicles and leaders. if I were to play a horde army I could sub pallies & strike squad for a rhino full of purifiers with 9 halberds, 1 daemon hammer. or 2 incinerators. i am working on a purifier list too, i am thinking 30 or so purifiers with rhinos.

Thanks, xxunphasedxx.

Suggestions:

Drop the psy ammo from the GM and LIB, not guna make that much difference.

Make sure both Term squads have a Psycannon - dropping more psy ammo if you need to. The 4 Psycannon shots will come in more usefull than the +1 strength to Storm Bolters.

Add a few Hammer's into your squads - they come free with the Terminators, I take at least one in each squad just in case.

For a Dreadnought loadout I prefer:
Twin Autocannon + Psy ammo 135pts
Multi Melta / Dread Close Combat Weapon (DCCW) / Incinerator (Heavy Flamer + Psyflame) 125pts

First off, welcome to the forums Brother!

Agree with Brother DOMIN4TRIX' suggestions. The psycannons will give you more punch than S5 stormbolters.

Thank you brothers, the advice is much appreciated.

xxunphasedxx.