I'm probably a little biased. But I'd recommend UEF, or failing this Aeon. As Cybran tends to be over represented in Ladder and it sounds like you'd prefer playing something which isn't as often used.
With UEF it is hardly accused of being over played. Especially in 1v1 Ladder. It definitely has it's own style, but, is in no way limiting. Many of the units can be rewarding for micro-management and it does have a reasonable variety of tactics. It is not simply a Ravager spamming faction. Here are some of the Pro's.
- Most powerful LAB. No unit rewards effective LAB play better than the Mech Marine.
- Awesome transport mobility options. With T1, T2, and T3 transport options UEF is very good at providing air mobility for it's ground units at all stages of the game. It's T2 Stinger gunships are even capable of lifting T2 ground units. Which can lead to some very interesting gunship/drop assault options.
- T2 Combat Engineers. The Sparky is awesome. It's fast, got the HP of a T2 tank, the DPS of a T1 tank, Jammer, Radar, and a T2 combat suite. It can shoots, and reclaims. I can decoy enemy shots, build T2 PD
and give that PD radar coverage. This unit is simply fantastic. It is an excellent battlefield reclaimer and makes a great addition to an army.
- Powerful navy. The UEF navy is strong.
- Powerful late game units. The UEF translates very well into the late game - and with their strong defensive capabilities you will have no trouble getting there.
- Very strong Air-to-Ground attack. While the Aeon are generally considered the superior air force. When it comes to actually inflicting air-to-ground damage the UEF is hands down the best. The Broadsword is far superior to Restorers when dealing ground damage. The Strat bomber has the best balance between AoE and damage. The Janus is an excellent carpet bombing tool. The Stork is a very good torpedo bomber... This when combined with their awesome transports - Not only is the UEF the most capable faction for air-lifting their ground troops, but, they are also highly capable at providing them with air support. So if you like playing "Starship Troopers" UEF is for you.