I have a slightly different vantage point of 1000 points as I'm an Ork player.
At 1000 points Orks are rather potent. The last tournament I played at 1k was Cities of Death. My list looked like this:
Warboss: Powerklaw, Choppa, Bonce, Eavy Armor, Iron Gob, Cybork
Stormboyz: (10) Nob w/ Powerklaw
Burna Boyz: (10) Mek w/ Kustom Force Field
Slugga Boyz: (16) Nob w/ Powerklaw, Burna x3
Trukk Boyz: (9) Nob w/ Powerklaw, Burna, Trukk w/ Grot Riggers, Armor Plates, Red Paint, and Rokkit Launcha
Looted Leman Russ: Hull Heavy Bolter, Armor Plates, Red Paint, Grot Riggers
Points: 992
If your playing your 1000 points in a tournament, your going to want 3 things.
1) A fast element to capture quaters and objectives. Whether they come on late or not, due to escalation, they can still do their holding job well by booking it straight for what you need.
2) A good core selection that is ready for anything. Most lists you will find at 1000 points will be lacking SEVERLY in one of the three phases: Move, Shoot, Assault. They will either take a bunch of fast troops, which lowers their model count considerably. They might take alot of vehicles, for 1000 points, which will generally hamper their survivability and anti infantry, because it is harder to root out troops in a building than it is to disable a tank with a single shaken result. Or they will take a large core force and leave themselves relativly immoble and prone to playing on your field. The trick to achieving this is to build a list that has elements of everything. You will have to sacrifice squad sizes and some wargear, but a well rounded force is essential at 1000 points.
3) A nice distraction, whether it be a juicy target, or the fact that you have too many squads on the table they they cannot effectivly focus fire on you, or your aformentioned Whirlwind. All are targets that present a problem to your opponent. your opponent will have to go out of their way to deal with any of them, and that is the purpose of the distraction. It is there to break up their normal tactics and make them think on their feet, which leaves more room for errors on their part. With my Orks I chose a Leman Russ.The reason I took my Leman Russ was to provide a suffiecent distraction from my Orks walking towards you. If you chose to fire at the tank then you lost shooting at the Boyz and vice-versa. It is hard with Orks, at this point level, to "Target Overload" you as they are so fragile, but it is definetly possible to present more targets, as Space Marines and Nids, to the opponent than he/she can deal with.
That is just my rundown on how I formed my list, which took 3rd out of 50 at our tournament. though there is also tactics involved. You have to complete your list on your own terms, so that it fits your play style. This is nothing more than a guide to hopefully help you break down the "needs" of a 1000 point list.
-Also, As far as
Dev squads go...I would probably mix Missle Luanchers and Heavy Bolters. You won't see much armor that your Missle Launchers won't be able to handle and Heavy Bolters are always nice. The more saves you force your opponent to take, the better chance you have at winning, and the Missle Launchers could still shoot frags to compliment the Heavy Bolters.