1500 first tournament list. Need help.

This Sunday after next, a small local games store that focuses more on card games and another tabletop games other then 40k are holding a 1500 point tournament I plan to attend. The only issue so far is that because it is a small place, I have no idea what sort of competition I'll be facing, and that because I have never been in a tournament before, I have no idea how to build a good list for one. So far my plan is to use my current 1500 points list which has been met with good (Not great) success, but after recently finding this forum, hopefully your advice can help increase my chances of winning.

HQ
Grand Master (220 points)
Sword, Stormbolter, Rad Grenades, Psycho Grenades, Blind Grenades, Brain Mines

Elite
Vindicare Assassin (145 points)

Troops
10x Terminators (495 points)
2x Psy, 3x Sword, 4x Halbard, 2x Hammer, Banner, Psybolt

10 GKSS (360 points)
2x Psy, 4 Halbard, 3 Sword, 1 MC Hammer (On justicar), Psybolt
Razorback
Assault Cannon, Psybolt, Dozer Blade

Heavy Support
Dreadnought (135 points)
2x Twin Linked Autocannons, Psybolt
Dreadnought (135 points)
2x Twin Linked Autocannons, Psybolt

Don't worry about "good list building". I am a strong believer that any list has chances to win. The general is what matters. keeping that in mind also consider what are you going to face in that tounament (often called the Metagame). Your list should be able to deal with that and also with the unexpected.

About your list, I think is looking good. A bit low in shooting but then again I like shooty lists. Perhaps droping the Vindicare for a third dread could add the firepower you so much need. You could also trim some points here and there and try adding a Librarian. Great unit for a death star (termies + lib+GM).
So good luck on the tournament and don't forget to post your battrep afterwards!

The only changes I would recomend is on the stirke squad changing the hammer to a normal guy and giving the justicar a halbard (this is for chalanges which he will find himself in and he will be going last against power weapons which will kill him before he gets to strike).
Also the terminaors in my opp need a warding stalf at 10 men, you can find points for this by droping the halbards on the strike squad, droping the blind grenades, droping the master crafted on the justicar, the dozer blades, brain mines or the psycho grenades (these are great, except for when you realy need them, and then you will normaly roll a 1). None of the things listed are needed and are only used some of the time. Keep the rad grenades as these work all the time.

I'd give that list a go. Your mobility isn't high with only a single transport and no jump troops so you might be forced to use 'spear of light' with your grand master if you're grabbing objectives across the board.