Okay, out of that list...here's what I'd recommend that you try to get (if you can afford it)...
Mass Effect 2...
Kasumi - Stolen Memory: Kasumi is one of my favorite characters and has some fun cameos in ME3. Also, you also get a VERY nice SMG out of this pack. For me, this pack was just a notch below Lair of the Shadow Broker, but that's probably because I have a huge crush on Kasumi.
Overlord Pack: This is not a MUST HAVE, but I really enjoyed the story and combat with this pack. (also, make sure you run over or shoot the cow-like animals on the planet for some giggles)
Most of the rest of the packs are weapon/armor packs...fun to spice up a new playthrough, but not necessary. The alternate appearance packs were mediocre.Firepower Pack: Adds three excellent weapons to the game. The Phalanx pistol is a VERY nice gun if you're into pistols...think pistol meets sniper rifle. It's probably the highlight of this pack. The geth shotgun and the Mattock assault rifle are both solid weapons as well.
Aegis Pack: This pack gives you a great set of armor (stat-wise), but I think it's a bit ugly personally (and it's not like ME2 is that hard to beat without better armor). The incisor sniper rifle that is included is a good choice for companions like Garrus, Zaeed or Thayne to use, but it's not ideal for the player.
Equalizer Pack: I didn't care for anything in this pack really. Then again, I tend to dislike most of the head armor and themed full-suit armor sets in ME. I'm a mix and matcher.
As for Mass Effect 3 (I'm SO glad they included the Extended Cut endings)...
Citadel - There is no other DLC in any of the games that matches up to this one. It is the cream of the crop. Pure hilarity will ensue.
Get this DLC. Also, I recommend putting off most of this content until you near the end of ME3. Some conversations with your crew members will reference side quests, but only if they've already been done. Much like on your ship, walk around your apartment a lot and just eavesdrop on the conversations so that you hear all of the dialogue between your companions.
From Ashes - I'm bummed they didn't include this one for you. I really recommend it. Javik is a highly entertaining (and cranky) companion, and he has some great moments in The Citadel DLC as well. I'd put this as a must have with The Citadel if you can afford both.
Leviathan - I enjoyed this DLC, and it did a lot to explain the origins of the reapers. I wouldn't say it's must-have if you need to pick your battles financially, but it's fun.
Omega - I'd put this in the same category as Leviathan, but I'd probably choose Omega between the two. Aria is an interesting character to me. Plus, you get a LOT of content with this. The battles are long (yet fun).
Groundside Resistance Pack - It's another weapon pack, but it gives you a pretty good bang for your buck with seven weapons being added. Still, I'd consider this very optional. The Executioner Pistol and N7 Typhoon Assault Rifle are the highlights.
Firefight Pack - And yet another weapon pack. This includes two of the best SMG's in the game (IMO) with the Blood Pack Punisher and Geth Plasma Submachine Gun, but I wasn't floored by the other guns. You can probably save your money.
Anyway, those are my thoughts.
I may be retired, but I'm GridStream for life.