Because 90% of the perks in the tree revolve around the super itself. Lets compare it to Bladedancer since these two supers are quite similar in a sense. Bladedancer has: - Quickdraw -Fleet Footed -Blink -A range of invisibility perks that has good synergy with Arc Blade and Blink Strike. Alot of the choices available are passive abilities that allow the Bladedancer to be very effective without ever having to use their super. Whereas the Sunbreaker's passive abilities are: -Fleet fire -Simmering Flames. Yes these perks are strong, but you would have a rough time trying to win a game as a Sunbreaker without ever using your super. Thats also assuming you chose these options in their trees. Say you chose Flameseeker in place of Fleetfire and Cauterize in place of Simmering Flames, you have an entire build based around one thing, there super itself. You replace passive abilities for one really strong offensive weapon. Without the Hammer of Sol itself, Sunbreaker Titans are a little underwhelming. The only change that could possibly be done would be to lower the armor benefit from Hammer of Sol, anything else could give Titans the Auto Rifle treatment.