While I respect your desire to flip your delver, you just don't have enough threats.
It looks like you started playing within the last couple of years, just based on card choices, so I'll try to keep my comments relevant to your available card pool.
Delver decks operate well with about 16 creatures, more if you have creatures (like your sage owl) that allow you to manipulate your deck. Ideally, you want 16 efficient dudes, costing somewhere between 1 and 3 mana tops. With only 9 creatures, you are going to be spending too many of your early turns digging for threats, and if one of them gets answered, it will set you back quite a bit.
Given access to mana leak, essence scatter and negate, dissipate doesn't need to be here. You can't afford to play spells that are that "expensive". 8 counters should be sufficient, especially if you have enough instant speed cantrips to help you find them.
Vapor Snag is fine. I don't think you need 8 unsummon effects, so 2 unsummons should be acceptable (for 6 total). You are running countermagic, after all, so you will be packing 11 card dedicated to preventing creatures from getting in your way.
The rest of your deck should be 1 and 2 mana instant speed
cantrips. You can keep 4 total ponder/preordains, but being able to draw cards during your opponents turn to try and find a counter or bounce spell is a big part of playing blue tempo.
If you can, I would suggest getting ahold of Brainstorm
, as both of these card exemplify the core of a delver tempo deck.
Depending on what creatures you choose, some sort of pump effects would be a good idea. I'm personally a big fan of Favorable Winds
, since most of your dudes should be flying anyway.
Lastly, if you build your deck out of mostly 1 and 2 cost spells (some 3's are ok) and enough cantrips (8-10), then you should be able to comfortably lower your land count to 18 or 19. After all, you only need a few, and the rest will be dead cards. Better to fill your deck with more answers.