Glads

2x Elemental Hero Prisma
1x Gladiator Beast Bestiari
2x Gladiator Beast Darius
2x Gladiator Beast Equeste
1x Gladiator Beast Hoplomus
2x Gladiator Beast Laquari
1x Gladiator Beast Murmillo
2x Gladiator Beast Samnite
1x Rescue Cat
3x Test Tiger
1x X-Saber Airbellum

2x Book of Moon
2x Enemy Controller
2x Gladiator Beast's Respite
1x Gladiator Proving Ground
1x Heavy Storm
1x Smashing Ground
1x Swords of Revealing Light

2x Bottomless Trap Hole
1x Call of the Haunted
2x Compulsory Evacuation Device
3x Gladiator Beast War Chariot
1x Mirror Force
1x Solemn Judgment
1x Torrential Tribute
2x Waboku

-2 Enemy Controller (if the deck doesn't use tribute monsters, there is no reason to run this over Book of Moon. It is good when it is versatile enough to find both effects usable)
-1 Respite (don't run more than 1, there's only so often you'll be able to use it anyway)
-1 SoRL (seriously, don't run this outside of a stall, burn, or exodia deck. It contributes nothing to the strategy of the deck, and is easily cleared from the field by the opponent if necessary)
-2 CED (not good in GB. In GB you want to maintain field presence and you want the opponent to attack into things like Shrink and Waboku)

-6 / +5 = 40 cards (please from now on mark how many cards are in your deck so I don't have to count)

+2 Proving Ground (These should always be MAXED!!! This is half of the consistency behind a GB deck!)
+1 Reinforcement of the Army (thins the deck and gets you Prisma. Don't forget that Prisma = Gyzarus. If you have Test Tiger in hand it is immediate. Otherwise, after he attacks he gets you Gyzarus)
+1 Waboku (Max this. No reason not to have maxed Wabokus in GB nowadays)
+1 Cold Wave (When this was unlimited, GB ran 3 and it made them uber powerful. Even though it is now down to 1, you still need to run all that you can! Cold Wave + Prisma is nearly game over)

I also suggest that if possible you should find ways to add in Shrink and a copy of Secutor. They're not as necessary as the other fixes but they're still very very useful. I'd say:

-1 Equeste
-1 Smashing Ground (you already have Murmillo and Gyzarus)
-1 Book of Moon OR the last Respite

+2 Shrink
+1 Secutor