I don't know that I've ever experienced extract twang (I've only done maybe two all-extract batches, and always added the extract late, anyway), but BierMuncher's
Centennial Blonde makes an awesome PM brew. I do it like this:
2.5lbs 2-row
0.5lbs Crystal 10L
0.5lbs Vienna
0.5lbs Carapils
Mash at 150F for 60 minutes.
Top up to boil volume if necessary (I usually boil 3-3.5 gallons), then start the boil:
0.25oz Centennial (10% AA) @ 60min
0.25oz Centennial (10% AA) @ 30min
0.25oz Cascade (7% AA) @ 10min
0.25oz Cascade (7% AA) @ 5min
3lbs extra-light DME @ flameout.
Chill, then top up to 5.25 gallons with spring water. Should get you an OG of 1.044 or so with 65% efficiency (I do stovetop PMs).
Ferment @ 64F until it's done. Carbonate it pretty spritzy.