31 flavors

I quick intro of my indecisiveness for Warhammer 40k.

I currently sport basically three armies, expanding into at least five.  Eldar were my first way back in the late 80s/early 90s, and again my first when I got back into it about 3 years ago.  When I was on my way to serve in Kuwait I started getting into Space Marines--I remember laying in my rack after training with a notepad dreaming up what kind of units I wanted to run--and so when I got home again, being single and having spent time where I could spend no money, I quickly bought a buttload of marines.  And of course I've always liked Chaos--my fantasy warhammer army back in the 80s (Khornate), and what's not to like about bad guys and big ugly monsters?

Eldar are my Tooty-Fruity.  What I like most about them is not the psykers or the tanks or the wraith constructs but the aspect warriors.  All superior specialists in the their fields and colorful to look upon.  I like to run lots of aspects and prefer Phoenix Lords to Farseers any day.  More recently, I've been trying to imagine a "fast and dirty" Eldar force, which lends more to Dark Eldar (very freaking cool in the latest revision, especially the models) and now the newest buzz is Eldar Corsairs, a list put out by Forgeworld.  I really like the idea and some of the things they've done, kind of best of all worlds attempt, though really, it's a best of Forgeworld attempt, as many unit choices are exclusively produced by them (funny how that turned out, eh?).  I will likely further explore that list and my own ideas at a later time.

I've heard codex Marines referred to as "vanilla".  I disagree.  I run my codex boys as Crimson Fists for many reasons: iconic chapter, maybe the most iconic chapter; I like the modern storyline with them being nearly wiped out, thus the hard-edged survivors, the underdogs of the Astartes universe; and really, I like the color scheme.  But vanilla???  No way.  The codex guys can be played a hundred different ways, depending on units and HQ and tactics.  And I rarely run the same list twice, though I have figured out my basic Marine list (and will explore that another time).  I also like Marines cuz I'm military and can relate.  I like the discipline and elite factor, and they're hardasses who take a big beating and keep coming.  I would like to play a horde army someday--really, if I were a billionaire I'd have one of almost every army, maybe not if only a millionaire--but I prefer the force were everyone counts and stands strong versus having to be okay with watching waves of your guys go down and hope sheer numbers works for you in the end.  As far as Codex goes, I also like White Scars and would probably give Ravenguard the time of day if I passed them on the battlefield.

Other Marine flavors I like: The green and bone of Dark Angels.  Cool storyline and style, but if I'm going to run a DA army it has to be the what makes them different.  Dark Angels have the Deathwing termies and Ravenwing bikers.  Never been that big into terminators but I really like bikes, and these guys compliment each other nicely.  The tricksy signature move for them is this: Ravenwing squadrons can make a scout move before the game begins, thus zipping across the field from the deployment zone, and all carry teleport homers.  The Deathwing can then deepstrike with upto half of their termie units on the first turn instead of having to wait for turn two.  Thus you zip your bikes in close before the fight, then teleport your best guys down right next to them on your first turn.  I also like that the deathwing can mix and match weapons within a squad (assault and shooty) and that if you take the corresponding HQs both wings can be Troops choices.
Another chapter I'd like to branch into is Space Wolves.  Again, story and style, and to play up to their flavor I would run wolfriders for sure, use more than 2 HQs (which unfortunately sucks up a lot of points), scouts who outflank like no other, Njal the weather master, and a pack of big bad wolves (not that effective but oh how cool!).

Blood Angels, I should note, are assholes but it's not their fault.  They are cool, I can see why you'd want to play them, but they're just too suped-up.  They're cheaters, designed with every super power and no real flaws (rage is not a flaw when it comes with furious charge and feel no pain and relentless and improved deepstriking and dreadnought psykers and land raiders as dedicated transports (thus no heavy slots spent)... you get the idea).  

And then there's Chaos, the original sin.  Another Tooty-Fruity ice cream cone if you drop it on the ground a few times and spike it with cocain, LSD, and razor blades.  I have come up with a lot of combos for them too.  Thematically, as long as the list has monsters and daemons and mean muthas, I'm good.