Don't listen to Jon Snow and all_sins_undone.
From what you've already described you like the softer side of Opeth without the growling
Good songs without growling: A Fair Judgment, Hours Of Wealth, Closure, To Rid The Disease, To Bid You Farewell, Harvest, Still Day Beneath The Sun etc...
Good songs to get into growling: The Drapery Falls, Bleak, Ghost Of Perdition, Reverie/Harlequin Forest.
Once you've gotten into growling, get the first 3 albums asap. (Orchid, Morningrise, My Arms Your Hearse)