Basing this on the stats released by curse about the new gladiator sets (http://www-en.curse-gaming.com/articles/details/2143/)...

Season 1 chest: 207 armor, 51 sta, 18 int, 25 crit, 24 resi, 32 spell dmg.
Season 2 chest: 438 armor, 57 sta, 11 int, 27 crit, 26 resi, 35 spell dmg.

Difference: +231 armor, +6 sta, -7 int, +2 crit, +2 resi, +3 spell dmg.

Season 1 shoulders: 155 armor, 42 sta, 13 int, 13 crit, 21 resi, 32 spell dmg.
Season 2 shoulders: 311 armor, 45 sta, 10 int, 13 crit, 21 resi, 35 spell dmg.

Difference: +156 armor, +3 sta, -3 int, 0 crit, 0 resi, +3 spell dmg.

Season 1 gloves: 129 armor, 39 sta, 14 int, 21 crit, 21 resi, 32 spell dmg.
Season 2 gloves: 283 armor, 42 sta, 15 int, 16 crit, 21 resi, 34 spell dmg.

Difference: +154 armor, +3 sta, +1 int, -5 crit, 0 resi, +2 spell dmg.

Season 1 cowl: 168 armor, 54 sta, 15 int, 18 crit, 30 resi, 37 spell dmg.
Season 2 cowl: 395 armor, 51 sta, 18 int, 20 crit, 31 resi, 41 spell dmg.

Difference: +227 armor, -3 sta, +3 int, +2 crit, +1 resi, +4 spell dmg.

Season 1 legs: 181 armor, 54 sta, 25 int, 28 crit, 30 resi, 42 spell dmg.
Season 2 legs: 410 armor, 51 sta, 27 int, 29 crit, 31 resi, 47 spell dmg.

Difference: +229 armor, -3 sta, +2 int, +1 crit, +1 resi, +5 spell dmg.

Total difference between season 1 and season 2:
+997 armor, +6 sta, -4 int, 0 crit, +4 resi, +17 spell dmg.

/golfclap Blizzard......