Need help selecting trees. I'm starting from scratch with an approx 60' X 75' open area, gently sloped from north to south. Current southern border is 4 Austrian pine (7' tall). One Autumn Blaze Maple (15') on eastern edge, one Yoshino Cherry (10') in NW corner. I'm looking for 2 lg. trees that -paired with smaller trees/lg shrubs- will provide good shade for a cool woodland atmosphere. Three sides (E,W,S) will be planted with either hedge, evergreen or latticed pergola walkway w/wisteria to keep down wind and winter damage. North edge is partially blocked by a building. Considered oak, but don't want acorns. Considered Sugar maple, but want to underplant. Already had bad experience with Ash and high winds. Any good lg. tree ideas for creating semi-dense shade with 10' space underneath in 20yrs or so? I'm willing to wait if it's the right tree. Thanks!