Cafrisun set = yes if you like to standard attack a lot (not oblique shot), and if you can afford it or farm it since Cafrisun spawns every 30 minutes now (big nerf patch), a lot of people camp cafrisun.
You may use Cafrisun set + Sacrament Buff (pardoner shop in town) until lvl 170 as a cheap set since enemies don’t hit very hard.
You can update your build in this thread at any time, so other forum users will know about this path/fun factor etc.
Elemental damage applies to all hits, including all skill hits. If you use a normal skill, you will hit +153 fire bonus damage per hit with arde dagger. Even if you use another element, such as Poison, each poison DoT tick will hit +153 fire extra damage. If you standard attack, you do +153 fire damage. If you have sacrament you will get an extra line of another +153 fire (and + holy sacrament damage), and cafrisun set is a third line of +153 fire +sacrament holy damage +12 earth damage. Sacrament adds +holy element to all attacks, similar to +elemental damage.
Old video, it still is like this: