If you're more in love with the concept of shield and spear as opposed to the mechanics of Phalanx Soldier, I think you should consider going with a Ranger with the Weapon and Shield combat style and use a short spear (one handed weapon).
Build wise, maybe something like:
Human Ranger
1. Power Attack
1. Improved Shield Bash
2. Two Weapon Fighting
3. Double Slice
5.
6. Shield Master
7.
9.
10.
Not sure off the top of my head how I would personally fill in the rest. The two weapon fighting style could also be worth using as it overlaps a bit with the shield style, but the real gem of shield style is Shield Master: being able to essentially get a +5 shield AND a +5 weapon for 25,000 gold is amazing, especially at level 6, plus not taking negatives for your shield attack is good stuff too.
I've got a phalanx fighter, only level 4 currently but I love him. I originally was thinking of Tower Shield + longspear, but the penalties on the tower shield hurt alot early on. Instead, I rock a longspear (at level 3, you can wield it one handed) and a spiked heavy steel shield.
Went with a Human Phalanx fighter, took power attack, furious focus, cleave, and combat reflexes. Wearing medium armour, with an ok dex of 15, and the shield, my AC is nothing to laugh at. Especially fighting with total defence when things are looking bad. At level 2, I was blocking the hallway so the wight couldn't use it's negative energy touch attack on the first level rogue, as the rogue plinked it to death with a shortbow.
The longspear has reach, so I threaten a 10ft radius with my 3 attacks of opportunity and if someone does get right up next to me, they rethink that when they eat my shield bash. If they try to run, they get stabbed, if they stay up close, they get bashed. The party rogue appreciates it, since it opens up more sneak attack potential, as well as generally gives her a safe zone to stay out of harms way. You can be really mean and get the "Pushing Assault" feat, which lets you forgo extra power attack damage to move the enemy away. This means, when I shield bash you with power attack, you eat attacks of opportunity from the spear on your next turn. The ability to use a longspear one-handed is a real treasure, that other sword and board type builds don't get to enjoy.
A gunslinger plays with us sometimes, and we were hunting goblins. I managed to kill four, with a spear and shield, while he only killed two with his Touch AC hitting firearm. And the best thing? We phalanx Fighters never run out of spells or ammunition.
I don't think there's a build you can go wrong with, but mine works well for me.