It is a combo deck regardless of whether you achieve infinite. You use 1 of 9 mana producing creatures to make a large amount of mana, which you then use to pay for 1 of 10 expensive spells that are essentially useless without some of the aforementioned 9 to pay. You then devote 4 slots to potentially pushing infinite, and 6 slots to tutoring some piece of the combo. It IS a combo deck.

Sylvan Caryatid is nice but it is unlikely to enable your win much more effectively. At the end of the day, you need one of the 9 big mana producers to have a chance at winning, infinite or not, and while your guy might put out somebody a little sooner or help with mana-fixing, or toss 1 more onto an X spell, it only helps you when you are already on the path to victory; it is a "win-more" mostly. Card draw, on the other hand, is good when you're ahead and amazing while you're behind.

I highly suggest switching blue sun's zenith for Genesis Wave because blue is the only color you can't go infinite with with bloom tender. With genesis wave you can turn 2) bloomtender turn 3) freed from the real, play whole library. If you have at least one Lightning Greaves you can take advantage of the haste for the activated abilities of all the creatures you just put down and swing with something big like emrakul.