Ok, let's consider a Fighter at level 12. He takes either: 2 levels of Fighter or 2 of Hero.
If he takes the levels of Hero, he uses his points to get the following abilities:
3: +2 Con (+14 HP and +1 Fort)
6: 3 feats
6: +4 Str (magical)
1: Increase Reach (Magical)
and has +1 BaB and 5 HP from levels
If he takes the levels of Fighter, he gets
1 feat
11 HP from levels
+2 BaB
4+ 2* Int skill points
+1 Fort save
In return for +1 BaB and skill points, the Hero gets 8 HP, +4 Str (so, +2 to attack and +3 to damage with a two handed weapon), Increased Reach (magical, but this is still an incredible ability) and 2 feats.
If he takes the levels of Hero, he uses his points to get the following abilities:
3: +2 Con (+14 HP and +1 Fort)
6: 3 feats
6: +4 Str (magical)
1: Increase Reach (Magical)
and has +1 BaB and 5 HP from levels
If he takes the levels of Fighter, he gets
1 feat
11 HP from levels
+2 BaB
4+ 2* Int skill points
+1 Fort save
In return for +1 BaB and skill points, the Hero gets 8 HP, +4 Str (so, +2 to attack and +3 to damage with a two handed weapon), Increased Reach (magical, but this is still an incredible ability) and 2 feats.