How long has you been shooting in competition beside these 3 idpa matches?
If you dont have any other experience or so few, just keep shooting with what you got. you already have a good gun. use it as it is. Once you get better, then start upgrading your gun.
I would suggest, DRY FIRE.. you will learn and improve MORE with drying firing than upgrading your gun with the best aftermarket parts or expending $2000 in ammo. really!
I dont know so much about those sights, but seems to be big for competition as far as I know but might be wrong. usually for competition you want a small fiber rod. Aiming at 20 yards at COM with a big fiber will cover the whole target.
rear sights black is good. I had a m&p with factory sight and I installed FO front and covered the dots in the rear sight.. then for my glock I got 10-8 performance rear and FO front.
you could check
http://czcustom.com/
good luck