Targeting drone with To hit buffs keep me from having to slot accuracy to my attacks. I went with recharge, damage, and a little bit of endurance cost reducers (I call them "Coolers". They keep my gun from overheating.)
Fully slotting the "Cloaking Device" (Its called something else now. I'm an old time AR/Dev blaster :P ) with many types of things. I slotted mine with Defense buffs and endurance enhancers. You can also slot health and coolers.
I like to play in groups, so I like to focus on the AoEs and the fast snipe (That may or may not be coming to all blasters soon) for bosses and hard targets. With just normal level 50 IOs I got the snipe down to 6 seconds. Burst is 2 seconds at the moment, and my shotgun blasts like slug and buckshot are 4.4 seconds. So 6 second CD on a snipe isn't bad in my opinion. Things will only get better with upgrade enhancements. :)
If your down with Soloing, or PvP perhaps, theres some interesting traps you can set up. The scary PvP build I used to use was great. Cloak up in a High traffic PvP zone and set up Caltrops. Then start stacking Tripmines. (Recharge and damage enhancements). Then Ignite. Then I would Teleport Foe into the mess and watch them either die instantly in an impressive blast that they can't get away from, or watch them get REALLY messed up and finish them with ease.
I don't know if you can still do it, but my SG and I used to farm warewolves with the stack of tripmines. I'd stack a TON of them and the tank would then gather the Warewolves and lead them back to the bombs. It was amazing! The blast knocked some of them so high... they never came down. (Not exaggeration) The damage wouldn't even say numbers. It just said "Error". Long story short. BOOM! XP!. xD
Hover is highly recommended. You're almost invisible, your smoke naids can be thrown without getting aggro, makes them only see at melee range, and if you slot it, can have an alright To Hit Debuff on them. If you wait for the tank (Or whoever is pulling) to get all the aggro before opening fire, most enemies won't pay you any attention. But for the few that will, they can't get to you if your flying, and the few that can... Web naid will place them on the ground for you. Or beanbag. Hover can also be slotted with even more defense if you like.
I like the defense debuffs Burst has. I went with Munitions Mastery. Surveillance does the same. LRM is really fun and can't hurt to ware the body armor. Blasters are soft.
Needless to say but I will anyway. Ya can't go wrong with Hasten. It may make your gun barrel a bit hot at times, but with endurance mods in Stamina and Cloak, mixed with the very few "Coolers" I have, I almost never run out of Stamina.
Now I've been an AR / Dev blaster from the time I was in the original Beta for CoH. That being said, I am not a mathematician, or an expert min/maxer (I don't do that really, but it can't hurt to try a little). So what I've said may or may not be the best suggestions. But I can tell you, that you will have fun with the class.