I'll preface this by saying that the build as-is is probably going to be able to do the campaign, but will have issues with post campaign content. So if your intent is simply to build a character you'd want to role-play without too much consideration to min-maxing, then it is perfectly serviceable.
If you are trying to build a min-maxing build however, I noted the following :
1) Con is not especially great for a secondary stat as you get a lot of HP from gear and base HD already. Pumping Con would basically be worth 200 hp or so at 40, which is about a 20% hp boost for a base 1000 hp character. Instead, I would pick either Cha (divine might, shield, bard cheese) or Dex (Robe AC, Champion of the Wild, Two weapon fighting) as the secondary stat to amplify AC and damage.
2) Elemental Warrior fits the RP concept well, but is honestly deadweight in terms of pure power. You lose 1 BAB simply by taking the first level, and the benefits (20% ranged conceal for limited duration) are simply not worth the cost. Frenzied Berserker for supreme cleave isn't bad, but late game enemies take quite a few rounds to kill, limiting the number of times cleave triggers and hence its usefulness.
Instead, I would pick either:
I) Barbarian 2 - Take the first barbarian level after 20 and you can take epic prowess instead of a rage type. This nets Toughness, Epic Prowess and Uncanny dodge as feats, and also allows access to one of the best non-set helmets on the server
II) Blackguard/Cleric or Paladin - For Cha secondary builds. This would give access to Epic Divine Might (2x Cha mod as unresistable divine damage), and divine shield (+5 Dodge AC). BG and Paladin options get huge save boosts, and the cleric option allows for domains (evasion for expose weakness is a strong choice).
III) Bard - With just 2 Bard levels and 25+ base Cha, it is possible to spend 4 feats to pump Inspire Courage to +6 AB/Dmg, and get a passive +2 AB with battledancer. Subtracting the lost BAB at bard 1, this is +7 AB/+6 Dmg for 2 levels and 4 feats. Low Cha builds get +5 AB/+4 Dmg for 3 feats. Note alignment clash with paladin.
IV) Champion of the Wild - For a dex build, dual scimitars with this would out-damage a single Falchion due to adding Dex mod damage and the huge number of extra attacks per round.
3) Fighting style - I see you did not take monkey grip, so I am assuming you plan on 2- handing the weapon? If you do so, you should take the shield skin feat for a 1+BAB/5 AC boost, or 8-9 AC at 40 for most high BAB builds. Alternatively, take monkey grip for a shield. This option gives +14 shield AC at the cost of about 15 damage per hit.
Finally, do plan on a 30 build before a 40 build, as the 30 -> 40 climb is extremely slow, and relevelling is relatively inexpensive on this server.