So I ran this deck through 2 leagues on MTGO. The first league I went 2-3 and then made some changes (8-10 cards. The second league I went 4-1 losing to hardened scales when on the draw and winning the one game on the play. The list below is what I most recently played.
Going forward I would probably not have so many counters in the sideboard or even the Pithing Needle
Also, I am not sure the maindeck needs 3 wishclaws and 3 finale so maybe those could be trimmed eventually down to 2
Some cards I tried in the first list but then removed
Tale's End
Apex of Power
Dig Through Time
Watery Grave x4
Going forward I would probably not have so many counters in the sideboard or even the Pithing Needle
Also, I am not sure the maindeck needs 3 wishclaws and 3 finale so maybe those could be trimmed eventually down to 2
1 Banefire
4 Botanical Sanctum
4 Breeding Pool
2 Doublecast
3 Finale of Revelation
1 Forest
4 Hidden Strings
1 Island
4 Lotus Field
4 Opt
4 Pore Over the Pages
4 Shimmer of Possibility
4 Sylvan Scrying
1 Blast Zone
2 Temple of Mystery
4 Thespian's Stage
4 Vizier of Tumbling Sands
3 Wishclaw Talisman
1 Yavimaya Coast
1 Watery Grave
4 Mystical Dispute
1 Pithing Needle
3 Spell Pierce
3 Thing in the Ice