I think this is all fairly balanced. Let's look at levels:
At first level, the one fighter will save 10% of the time versus Reflex whereas 90% of the time, the result is the same. Ditto for the fighter with the Will save. If low level spells are 10% Fort, 45% Reflex and 45% Will (there are only a small handful of low level Fort spells), that means that one spell in 22 has its result changed. 21 spells out of 22 are unaffected. This is not game breaking.
At 20th level, this changes to 30% of the time. If high level spells are 20% Fort, 40% Reflex, and 40% Will, that means that one spell in 8 will have its result changed. So, it might help once per day in a 4 encounter per day situation. And of course, this assumes that the fighter does not take a prestige class which is basically unheard of. Compared to prestige class abililities, this is not unbalanced, in fact it's pretty weak.
Hit points will be +2 at level one and +40 at level 20. However, this is only about 20% extra hit points (give or take) each level. That means that this fighter will survive for maybe an extra round or two compared to normal at most levels. Helpful, but not unbalanced. Probably slightly stronger than the other three and used more often, but +1 per level would not be strong enough.
That leaves the skill boost. I think this one would be taken by many players, just because it opens up certain RPing and Prestige Classes easier. Not typically as useful in combat, but it does give the player more options out of combat which I think is nice.
All in all, none of these sound unbalanced and they seem to balance against each other fairly nice except for the hit points which is slightly stronger, but still not overwhelmingly so.
At first level, the one fighter will save 10% of the time versus Reflex whereas 90% of the time, the result is the same. Ditto for the fighter with the Will save. If low level spells are 10% Fort, 45% Reflex and 45% Will (there are only a small handful of low level Fort spells), that means that one spell in 22 has its result changed. 21 spells out of 22 are unaffected. This is not game breaking.
At 20th level, this changes to 30% of the time. If high level spells are 20% Fort, 40% Reflex, and 40% Will, that means that one spell in 8 will have its result changed. So, it might help once per day in a 4 encounter per day situation. And of course, this assumes that the fighter does not take a prestige class which is basically unheard of. Compared to prestige class abililities, this is not unbalanced, in fact it's pretty weak.
Hit points will be +2 at level one and +40 at level 20. However, this is only about 20% extra hit points (give or take) each level. That means that this fighter will survive for maybe an extra round or two compared to normal at most levels. Helpful, but not unbalanced. Probably slightly stronger than the other three and used more often, but +1 per level would not be strong enough.
That leaves the skill boost. I think this one would be taken by many players, just because it opens up certain RPing and Prestige Classes easier. Not typically as useful in combat, but it does give the player more options out of combat which I think is nice.
All in all, none of these sound unbalanced and they seem to balance against each other fairly nice except for the hit points which is slightly stronger, but still not overwhelmingly so.