I hope I haven't made a big mistake.

I want to pursue the main quest line for the Thieve's Guild, but the Dark Brotherhood was ... too dark for how I wanted to play my character.

So I killed Astrid, which started the "Destroy the Dark Brotherhood" quest, and I put it on a back burner long ago (haven't pursued the quest).

But I just recently discovered that the Thieve's Guild is closely linked with the Dark Brotherhood. So have I messed up my ability to continue with the Thieve's Guild quest line? I'd rather find out now than later on, so I can decide whether it's worth going way back to an old saved game before I killed Astrid.

Also, does pursuing the Blades quest line interfere with pursuing the Greybeards quest line, or visa-versa? I'd like to do both, ideally.

One more question: My Sneak skill has reached 100, and I have all the Sneak perks in the left branch (and most of the rest). Level 33, if that matters. Do things like amulets that boost your sneak ability have any effect at this point?

Thanks!

nope. your in the clear. Other then references to the Dark Brotherhood from Mercer Frey.. odd letters and what not. Your in the clear.

I think if you do what Delphine demands and kill the greybeards will no longer direct you to words of power.

I don't know about sneak at 100 and use a amulet for it. I use lock picking and pickpocket rings/amulets for my thief since my sneak is also 100 with both sides of the tree filled.

and one thieves guild member who used to have contacts or used to be a member of the brotherhood. cant remember which it is, but he stays at the thieves guild the whole time. no unless it causes some random glitch it shouldn't mess any thieves quests up.

1:No,you haven't messed with the thieve's guild Questline(but you missed some nice things from the DB)

2:Yes,if you do the blades questline,and kill Paarthunax,Arngeir will fus ro dah you off the 7000 steps(this will hurt a lot)

3:Yes,sneaking enchantments will have normal effect.

Mercer Fray and Delvin both have Dark Brotherhood contacts. There are notes even found in Mercer's desk from Mavin about hiring the brotherhood and who not to hire the brotherhood on because the person still had value. Plus maven has that secret room in her house were she performs the dark sacrement...

My thief plans on killing the brotherhood since she is the new Guild Master. Just gotta find a way to RP that part into her story. I think I have it covered.