The Normal Raids are nothing like Coil when it comes to difficulty - they're much, much easier and even DF-groups will clear them easly in 95% of the cases.

After people complained that they werent able to experience the Coil-story since it was locked behind the most difficult content in the game at that time, they changed their approach with HW: We got two versions of the raids - the "normal mode" (NM) that is included in the roulette you mentioned and the Savage version.
The NM is close to your usual MSQ-primal - it has mechanics, you can fail, but the required communication is minimal, people dont even really need to know what they're doing in the first place.
Savage is close to (original) Coil difficulty - everyone needs to know mechanics, you're wise to use some voice-chat, buffs, food... pretty much the raiding experience for statics now.

Bottomline: Go ahead and do those NM! Queuetimes for the old ones might be a bit slow and the exp-payout of that roulette isnt all that great, but some of the fights are pretty fun! Going in blind shouldnt be a problem either, they're no mechanics that would be an instant fail. I cant recall any tank-sawps or the like in the NM-versions right now either.
Just a little bit of a warning: People outgear this content so much by now that some fights are a real joke and over before you got a chance to properly enjoy the music!