I don't know how much this helps Phys, but here is a look at Commando from stat respeccing:

NOTE:All statistics are without gear equiped, and at lvl 21.

Lv 21 Commando: 105 STR, 3 DEX, 1 INT:

Hit%: 70
Crit: 2
Dodge: 2
Health: 208
Health Reg:2
Mana:134
Mana Reg:1
DMG: 11-12
DPS:15
Armor:4

Skills: Name and Damage at Lv 1

Force Hammer: 11-15
Neutron Stomp: 11-15
Gravitron Slam: 11-18

Lv 21 Commando: 5 STR,103 DEX, 1 INT:

Hit%: 73
Crit: 2
Dodge: 2
Health: 183
Health Reg:1
Mana:109
Mana Reg:1
DMG: 9-10
DPS:12
Armor:3

Skills: Name and Damage at Lv 1

Force Hammer: 9-13
Neutron Stomp: 9-13
Gravitron Slam: 9-16

Lv 21 Commando: 5 STR,3 DEX, 101 INT:

Hit%: 68
Crit: 2
Dodge: 2
Health: 158
Health Reg:1
Mana:139
Mana Reg:1
DMG: 7-8
DPS:10
Armor:2

Skills: Name and Damage at Lv 1

Force Hammer: 7-11
Neutron Stomp: 7-11
Gravitron Slam: 7-14

Currently, I use the Lv 20 Plat gear which provides 2 dex, 155 health, 152 mana, and 320 armor. It is pretty obvious that STR is the way to go with Commando. (Rhyme not intended. ) When looking at key attributes in the game, we see:

Hit%: Dex>Str>Int (but only by 3%)
Crit: Push across the board
Dodge: Push
Health: Str>Dex>Int
H/S: Str>Dex=Int
Mana: Push
M/S: Push
DMG: Str>Dex>Int
DPS: Str>Dex>Int
Armor: Str>Dex>Int

The same can be said for skill distribution, as Str clearly provides more skill damage than the other two categories.

Now, will all of this ALWAYS be the case? Who knows. With new updates, changes in gear, and multi-class weaponry/gear, the ability to add/subtract to/from different attributes will always effect things, just as it does in PL. But for now, just like with the Op, it appears that STR provides the best overall spec for Commando.

Hope this helps, Phys. My apologies for the lack of statistical analysis (I always hated math!!)