Your Deck looks pretty good in a vacuum but you need to have answers for what other people are doing.
the easiest way to do stuff is to have cards so i'd recommend
-Beast Whisperer as it is an elf
-lead the stampede as it works about as well as harmonize
-shamanic revelation to refill hand if you have a built board.
A lot of strategies count on the commander so you need to be able to stop it.
you already have beast within which is a great card.
-Lignify
_kenrith's transformation
Both turn a problem creature into a not problem creature. Best of all neither removes the creature from the field so the commander is stuck as a 3/3 elk or 0/4 tree until someone kills it.
Speaking of killing, People like to do that to your things a lot.
-Heroic intervention. 2 mana to just say no to a board wipe or fizzle targeted removal
-wrap in vigor. basically a worse heroic intervention that can still save your board.
-Resuscitate. even worse wrap in vigor but you're an elf deck you have the mana. essentially its a one time use of ezuri's regenerate ability.
Looking at your deck I wouldn't say you need to add all of these cards, but I would return to this list after playing a couple games to see what you need to go against
the decks you face.
Lastly some cool elves you might not have seen
-Arbor elf is another one drop mana dork
-llanowar tribe just 3 llanowar elves stuck together
-llanowar visionary - ramp and draw
-paradise druid hard to kill
-roflellos makes a stupid amount of mana
-heritage druid has a trick where you can tap creatures that just enteres the battlefield for mana
Lands are cool and you wanted some besudes basic lands
-mosswort bridge gives you esentially a free card
-castle garrenbrig lets you ramp with a caviate
- arch of arazca lets you draw cards
-bonders enclave does the same thing
- ghost quarters removes other high impact lands
-field of ruin does the same