I think it would be fun to have titans in dark realms sometimes.
Reason: It would completely re-balance the whole thing, making it impossible for just 1 or 2 players to win against a guild with 10+ hunters, since they wouldn't see the titan across the map, and since a guild that covered the whole map with their members would see the titan immediately.
Just my 2 cents 
I don't think we need to make it any easier for the 10+ players to win over a 1-2 player guild, since the larger group already has that going for them. If anything, a 1-2 person guild that can take down a larger guild in Titan hunting should get a bonus! Don't punish people just for being smaller, being in a 124 person guild isn't for all.