Aight, so this turned out much worse than I expected, but it also has some advantages and.... It's different!
In summary, I think the wizard 24/druid 6/shifter 10 is much better AC/AB, even though it's temporary. The only advantage of the weaponmaster helmed horror seems to be its crit range and damage.
Base Race: Human
Alignment: Any Neutral
Starting (final) Stats:
Str 8
Dex 15 (18)
Con 8
Int 14
Wis 18 (27)
Cha 8
I've specified which class you're taking by writing # (Class), which means every level thereafter is that class until you see a different class in parenthesis.
1 (Druid) - Alertness, Dodge
3 - Weapon Focus (Scimitar recommended)
4 - Wis +1
6 - Mobility
7 (Shifter)
8 - Wis +1
9 - Spring Attack
12 - Wis +1, Expertise
15 (Druid) - Whirlwind Attack
16 (Weapon Master) - Wis +1, Weapon of Choice
18 - Weapon Proficiency Martial
20 - Wis +1
21 - Weapon Focus Greatsword
24 - Wis +1, Improved Critical Greatsword
27 - Blindfight
28 - Wis +1, Weapon of Choice Greatsword
30 - Great Wisdom 1
31 - Epic Weapon focus Greatsword
32 (Shifter) - Wis +1
33 - Construct Shape
34 (Weapon Master)
36 - Dex +1, Great Dexterity 1, Epic Prowess
37 (Druid) for 40 spellcraft (+8 saves vs spells)
38 (Weapon Master)
39 - Armor Proficiency Heavy or Toughness
40 - Dex +1, Armor Skin
The attack schedule, unbuffed, and in shape is going to be 60/55/50/45 at 13-20x3. The good news here is the +6 weapon is the only thing that adds to the +20 AB cap; which means there's a theoretical +14 you could get from party buffs...
I recommend stocking up on Bless and Aid potions for 62 AB.... and haste potions if you can get your hands on them. The only place I know that sells bless/aid pots is the little shop in Moria.
The AC is much less than expected at:
10 Base + 2 Armorskin + 4 Tumble + 7 Dodge from Shifting + 6 Armor + 6 Shield + 6 Deflection + 6 Natural Armor + 4 Dodge from Boots + 4 from Dexterity + 6 from fully buffed dexterity (+12 to Dex) = 61
I guess the good news here would be traveling with a bard - with song and haste you have 71 AC. Not great either.... but higher than the cleric! Capped at 66.
You can use expertise mode to boost your AC by +5, but you lose 5 AB of course.
You're going to have a hard time maxing your important stats like str/con/dex without outside help methinks...
If you plan on doing this, I'd assemble a crack-set of gear before hand so you're not totally disappointed....