The Gamer pack V2 is a medium weighted modpack that has a lot of adventure and lots of things to do. Within this modpack you can build very crazy buildings with Chisel and make cool structures with Carpenter's Blocks.
This modpack has lots of places to explore with the nether being updated with Natura. Maybe you want to battle people in the Twilight Forrest. Or even set out for a mission into the stars with Galacticraft.
With lots of things to do you will be playing for hours on this modpack.