Is a Greatspear a good choice for a Paladin?

Question

I have been told to build a Dragonborn Paladin and was wondering if the greatspear would be a good choice at level 1. If so, do I need a proficiency feat? The stats for that are:

Superior two-handed polearm
+3 with 1d10 (Reach)

If I can use this, are there any feats or abilities that would complement this weapon and its range? If not, are there any weapons that would work better?

Answer 1

No, reach is a bad choice for a paladin.

A paladin's divine challenge requires:

The mark also ends at the end of your turn if you didn't engage the target, meaning you neither attacked it during your turn nor are adjacent to it at the end of your turn.

While nominally a single-target challenge requires attacking the enemy anyways, and a greatspear can do that, a defender wants to control the battlefield and ensure that enemies she's marked don't run off to bother the squishies. The wording of the mark only compounds that desire.

A reach weapon isn't crippling for a paladin, but it is a malinvestment of resources.

Answer 2

If you want a polearm, Greatspear is a good choice because of its accuracy. It costs a feat (Weapon Proficiency: Greatspear), but it is worth it.

However there are only 4 good reasons to use a polearm for any class:

1. Polearm Momentum for control. You should not have the 15 Dex for this, but even so, you do not have enough pushing and sliding powers.
2. Polearm Gamble for control and damage. However no enemy in their right mind would approach the guy with the heavy armor and low damage. Unless you expect to spend your life in 3 squares wide dungeons, you will not benefit from it. Works best with Polearm Momentum anyway.
3. You have bad defenses, but you still want to attack the target in melee. Basically this means you are a Leader.
4. There are too many melee characters in your party, and you are unable to get adjacent. This is the land of party optimization. Basically, do not play a melee character in this case, if you must bring a defender create a Wizard|Swordmage hybrid.

A Defender's job is to limit the enemie's options. If you are adjacent, you do not have to attack the target of your Divine Challenge to keep up the mark, and more importantly, you can make an Opportunity Attack against the enemy if it moves away.
Reach is only good if you want to stay away, but as a Defender, you should not want that.

I would say you are better off with a Longsword and a Heavy Shield. Better defenses, less investment.