Pretty cool sun team.Like previously stated special dragons such as Lati@s is a major threat.It outspeeds 5 out of 6 of your pokemon in sun and all of them outside sun and easily land several kills.They can even pull of a sweep with Specs Dragon Pulse.Heatran also causes a lot of trouble.
I don't have much experience with Sun teams so I can't really give you a solution for sure but I think using
Sawsbuck as your chloro sweeper will help a lot against Special Dragons and Heatran,two of this team's biggest threats.Thanks to it's 95 base speed you can afford to run adamant so you'll be able to outrun and smack the Lati twins hard with LO STAB Frustation/Double Edge in sun and destroy heatran with EQ(Nature Power) or Jump kick(less reliable since heatran carries protect).You don't really lose out much that Venusaur had so i think it's worth to consider.
The set
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