I am most familair with Paladins, so I'll just comment on them.
They need some progression on smites. Perhaps one every 5 levels? Or even 6 levels.
The mount needs work. The way Magical Beast works for the mount needs to be clarifed. This simplest way to do this is simply make them a "Magical Beast" per the Monster's Manual with the added powers/features they get as the Paladin advances.
They also should advance more often.
The bonus to Natural AC needs to be clarified
My suggested version is (areas I changed are in bold italics). The gaining of the Celestial Template may seem like a bit much, but it gives a reason to stay pure Paladin to 20th level:
PALADIN'S MOUNT
The paladin's mount is different from a standard animal of its type in many ways. The standard mount for a Medium-size paladin is a warhorse, and the standard mount for a Small paladin is a warpony. A paladin's mount is a magical beast, not an animal. It has an alignment of LG. It is superior to a normal mount of its kind and has special powers, as shown below
Paladin.....Bonus.....Natural.....Str
Level........HD...........Armor.......Adj........Int.......Special
-------......-----........-------.......----........---.......-------
5–6..........+2.............4.............+1..........6......... Improved evasion, share spells, empathic link, share saving throws
7..............+3.............5.............+1..........6..........--
8–9..........+4.............6.............+2..........7..........--
10............+5.............7.............+2..........7..........--
11–12.......+6.............8.............+3..........8..........Command creatures of its kind
13-14.......+7.............9.............+4..........8..........--
15–19.......+8............10............+4..........9.........Spell resistance
20............+8............10............+4..........9.........Celestial
Paladin Level: The level of the paladin. If the mount suffers a level drain, treat it as a mount of a lower-level paladin.
Bonus HD: These are extra eight-sided (d8) Hit Dice, each of which gains a Constitution modifier, as normal. Remember that extra Hit Dice improve the mount's base attack and base save bonuses.
Natural Armor: The number listed here is an improvement to the mount's natural armor. It represents the preternatural toughness of a paladin's mount.
Str Adj.: Add this figure to the mount's Strength score.
Int: The mount's Intelligence score.
Improved Evasion: If the mount is subjected to an attack that normally allows a Reflex saving throw for half damage, it takes no damage if it makes a successful saving throw and half damage even if the saving throw fails. Improved evasion is an extraordinary ability.
Share Spells: At the paladin's option, the paladin may have any spell he or she casts on him or herself also affect her mount. The mount must be within 5 feet. If the spell has a duration other than instantaneous, the spell stops affecting the mount if it moves farther than 5 feet away and will not affect the mount again even if the mount returns to the paladin before the duration expires. Additionally, the paladin may cast a spell with a target of "You" on the mount (as a touch range spell) instead of on herself. The paladin and the mount can share spells even if the spells normally do not affect creatures of the mount's type.
Empathic Link: The paladin has an empathic link with the mount out to a distance of up to one mile. The paladin cannot see through the mount's eyes, but they can communicate telepathically. Even intelligent mounts see the world differently from humans, so misunderstandings are always possible. This is a supernatural ability.
Because of the empathic link between the mount and the paladin, the paladin has the same connection to an item or place that the mount does, just as a master and his familiar.
Share Saving Throws: The mount uses its own base saves or the paladin's, whichever is higher.
Command: The mount's command ability is a spell-like ability that it can use at will against other creatures of its kind with fewer Hit Dice than it has itself. The mount can use this ability once per day per two levels of its paladin, and the ability functions just like the spell command (for purposes of this spell, the mount can make itself be understood by any normal animal of its kind). Since this is a spell-like ability, the mount must make a Concentration check (DC 21) if it's being ridden at the time (as in combat). If the check fails, the ability does not work that time, but it still counts against the mount's daily uses.
Spell Resistance: The mount's spell resistance equals the paladin's level + 5.
Celestial. The mount becomes Celestial. The mount gains the "Celestail" template per the Monster Manual.
