Skip Dragonball GT, it is not cannon, unless you do not care then i'd say watch it with Dragonball Super.
Also Kono Subaru is only 10 episodes, it is based on your RPG/MMORPG games with comedy in it.
Really funny to watch, def. recommending watching Kono Subaru as a side anime for a quick laugh between your more serious anime like Naruto or Re:Zero.