Budgeting for complexifimication

I have been busy rebuilding my monster list for Heroes By Trade.  One of the things I have been wrestling with is just how complex I want monster stat blocks to be.  There is a tricky balance to achieve here between offering detail and flexibility of design on one side and ease of use on the other.  As an example I have randomly yanked a monster from DnD 4th edition that is of moderate complexity for that system and I will compare it to a moderately complex HBT monster.

DnD 4th:

Aboleth Lasher Level 17 Brute
Large aberrant magical beast (aquatic) XP 1,600
Initiative +11 Senses Perception +14; darkvision
Mucus Haze aura 5; enemies treat the area within the aura as
difficult terrain.
HP 200; Bloodied 100
AC 29, Fortitude 27, Reflex 25, Will 25
Speed 5, swim 10
Tentacle (standard; at-will)
 Reach 2; +20 vs. AC; 2d8 + 8 damage (4d8 + 8 damage against a
dazed target), and the target is dazed (save ends).
Combat Advantage
 An aboleth lasher makes an extra tentacle attack against any
enemy it has combat advantage against.
Alignment Evil Languages Deep Speech, telepathy 20
Skills Arcana +19, Dungeoneering +19, Insight +19
Str 26 (+16) Dex 16 (+11) Wis 22 (+14)
Con 20 (+13) Int 23 (+14) Cha 17 (+11)

HBT:

Bone Hound		ES    5
Size    1		Speed    6
Dodge    14	Armour    4	KO    25
Knockdown:  +4 Hit, +6 Damage and knocked Prone. Ravage:  +4 Hit, +6 Damage and Stunned for 1 round.  Only usable on Prone targets.
Undead:  Immune to Afraid.  Falls to dust when KO.

The Aboleth definitely has a more complex stat block than the Bone Hound.  Part of that is the fact that it has more defensive stats to deal with but also there is a bunch of extra information packed in there.  The Aboleth has listings for combat role, stat and skill bonuses for resolving noncombat situations, languages spoken, XP, and slightly more complex combat interactions.  Some of these are junk that I don't think should be in the system at all such as combat role and XP but I am on the fence a bit about things like stat bonuses and skill numbers.

I definitely feel like DnD 4th was too heavy on the preparation required for combat.  Monsters simply had too many options and too many numbers to keep track of.  HBT has much less combat option bloat and that is a good thing in my mind.  I want the GM to be able to figure out if hits land very quickly and that is much easier to accomplish in HBT than DnD 4th.  Also there were a huge number of monsters with all kinds of reactions that took place during opponent turns and abilities that triggered off of hitting the Bloodied health number and such.  Keeping that all in mind for a half dozen enemies at once was just too much of a pain.  HBT monsters have less wacky stuff going on which is unfortunate in that an omniscient GM has a little less to work with but it is an overall gain because combats flow much more quickly and new GMs aren't completely overwhelmed.

They also had completely bizarre stat blocks that made no sense whatsoever - I can't imagine why every high level opponent would have the mind of a transcendent genius even when it is just a big brute that punches players with tentacles.  I think I may want to include Strength, Intelligence, etc. scores in HBT stat blocks because I do want people to think of alternate ways to engage with monsters aside from murder but I really do want to avoid excessive information on the page.  Everything I add in makes it more difficult to find the most useful information quickly.  I definitely want to avoid having every high level monster have enormous mental scores for no appreciable reason.  On the other hand I am pretty okay with gigantic beasties having massive Strength scores!

Of course there is a lot more to a monster entry than just the raw numbers.  I want to have sections that focus on the social structure, language, culture, and biology of the various creatures I describe.  Fitting in all kinds of neat extra stuff that places the creature in the world organically instead of just as a combat obstacle makes things feel a lot more real for everyone involved.  The combat block has to be maximally functional for a GM who wants to quickly and easily run a combat with the creature but the rest of the entry needs to support world building, particularly when players read the monster entries just for interest or entertainment.  I want it to feel like an ecosystem rather than a game structure as much as I can.