The best beginner blend? There is none. Pick a style of tobacco, read reviews and smoke some. Get three dedicated pipes, one for latakia, one for all aromatics, and one for everything else. You'll end up getting more pipes eventually but for now get all cobs from Missouri Meerschaum and use the cost savings for more tobacco. You need to smoke and try some more. It never ends. You're always smoking new blends and old friends. That's what makes this hobby interesting.
If I had to pick a place to start try tobaccos sold bulk in ounce increments. Boswell makes Pipers Pleasure and Penn. Dutch Treat, Sutlif makes Vanilla Custard and Z50 Black Cordial for aromatics, Virginias try Newminster 400 or Peter Stokkebye 402, for Oriental try Oriental Silk, for Burley try Boswell Prem. Burley, CD Pegasus or MacB Golden Extra, and for Va/per try Boswell Private Stock Vaper or Peter Stokkebye 400.