Drafting the blue half like Draw Two. Lakeshore Apothecary (52.4% here, 58.7% in Draw Two) and Master's Councillors (52.8% here, 59.6% there) only work when you draw a second card each turn, and a Draw Two deck has twice as many cards that do that, because white's cards come on top of blue's.
Expecting blue's to carry the deck. Uneasy Partings (53.6%) and Enchanted River's Grasp (53.4%) do worse here than in Draw Two and sit only a little above the deck average, and these colors have no cheap, unconditional kill spell. Play every removal spell you get, but plan to win with the board. Take Quarrel early, and value the Elf cards (Woodland Weavemaster, Wood Elves, Down in the Valley) at least as highly as the blue removal, because in this deck those cards do as well or better.
Playing your land after combat out of habit. bonuses like Attercop's +1/+1 and Boughside Wanderers' +2/+2 last until end of turn, so play the land before you attack. The exception is an uncracked Hobbit Hole or Elven Passage, which you crack after blockers are declared.
Ramping into big green cards that lose. Gigantic Big Bear (52.4%) is only at the deck average although drafters take it around pick 3, and Beorn, Reluctant Host (48.2%) and Wilderland Scrounger (48.9%) are well below it. Your late game is Mirkwood Pathmaker, and counters.
a land with Mirkwood Nurturer when you have lands in hand. You get one land drop a turn, so the returned land replaces the new one and you fall a mana behind. Return Wood Elves or Bilbo Baggins, Burglar instead.
Counting a second Thranduil, Sindarin Liege or a second copy of the same Bilbo as a full card. They are , so two copies with the same name can't stay on the battlefield together. Bilbo, Luckwearer and Bilbo Baggins, Burglar have different names, so one of each is fine. A second Thranduil is still fine for its Silvan Rally half.
Cardsplain