Even though he is stated to be one of the top character cards there are very few decks surrounding him. Lets take a look at his character Card.
F: Discard any number of cards: Add 1 card of diddcultiy x or less from your discard pile to your hand. X equals the total difficulty of the discarded cards. Only playable once per turn.
E Commit 1 foundation: This attack gets x=1 damage. X equals the number of times this enhance has been played this turn.
Omar's F lets him fish for cards in his discard pile that he needs. While his E is stackable and allows him to damage pump. Lets look at his pro's and then his cons.
Omar's biggest pro is built in fishing. There are few cards that let you fish cards. There aren't any cards in the meta that let you fish any card you want from the discard pile. This is a unique and powerful skill. This can allow him on turn one to turn a bad hand into a decent hand after a few checks. Omar's E being able to stack on itself is crazy when you think about him stacking cheap attacks that do low damage. He can make a string of attacks into a decent damaging attack.
Now lets look at his cons. Most people are not going to run character cards with him. This means that better attacks are going to cost you 2 cards to fish. Add on the fact that some decent 4 difficulity foundations may cost you two cards to retrieve. His E is going to make you go through your deck fast just off his own ability. Its funny that he has the possability to mill himself if he gets established. But his abilities don't move toward quick kills. Without speed and damage pumps Omar is straggling behind the top tier cards. The next con with Omar is his symbols. Some might scratch their heads when I say this. Omar needs speed pumps. He can get some from All but the best speed pumps are in Life right now. Not only that Chaos gives him more damage pumps which he already does. Earth's main strength right now is throws and Ras and King do the job better then Omar. Even Seig to some extent can out damage tempo off of earth then Omar. Feel free to look up the Seig throw deck for reference.
Earth can give Omar throws but other Earth Characters do better with throws then he does. Lets look closer at that. When it comes to throws King can fish throws and play them for free if they are 5 check or less. King's throw support does a lot to pump the damage of throws. Now with that you are better off commiting 1 foundation and playing its ability then commiting it to do x+1 damage. Omar's E has to be used 3 times before his e starts outpacing King's support. While it could be said he was built for master of magic/Yimrfang combo, he lacks the consistant damage to push it through. It is easy to over extend with him to make your opponent cry a bit more. Good news is you have access to anti commit tech.
When we look at Chaos closely we got to cry a bit for the fact he can't use Alshain Najm combo since it is algol only. There only 2 throws he can use. The first is Alphard Maliki, the second is double face kick. Both attacks are must for running Omar off of chaos. Lack of throws puts Omar at a disadvantage right now. The good news is that you can play Zi Mei's attacks. The bad news is that your playing the same attacks everyone else in the meta is playing. Unlike fire, chaos lacks the added push to make Zi Mei's attacks beastly. Add on the fact that Willful and Invoking the Ancients are your only speed pump is saddening fact.
All might be where the party is at. The throws are just as limited as before. Pummel Smash, Hammer of the Gods, Lunging Brush Fire abuse, Odin's Wrath, and some other nice goodies welcome you with cake and pie. Genius Alchemist, Finicial troubles, Relentless, The Ultimate team and new commers are in your welcoming package. The thing is there is a lot of draw. Thing is draw is nice but again your going through your deck fast. Your damage pumps from all are Bloodline Rebellion, Its Got to be the hair, Rivarly with a bear, and the ultimate team. Purified body, graceful style can give you a speed boost. Its not much but it beats chaos zero speed boosts.
I would say if Omar was life he would be broke. He would have the speed to push any attack he wanted through and get the damage up so he could kill fast. Who knows someone may do a needs no ally deck with that idea in place.
One thing Omar is not lacking is access to draw and damage pumps. But he has no strong control elements and doesn't have any strong speed pump access. As the symbols flesh out a bit more he will give some of the top cards a run for their money. It would first require Fire not to get pumped much more, All getting some more speed/stun support independent of fire. Chaos getting a control element that is not based on a gimmick.
Currently I am testing a Omar chaos deck using Kazuya's support and Cervantes check support. Its been a back and forth between him and my King deck. My king deck kill Omar by turn 4 or 5. If Omar keeps the pressure on he can make King hurt but it requires him to plan more and getting Devil gene early. The biggest weakness of the deck is that it can fish any card it needs because I pack character cards, but if I don't draw or discard key cards I can be stuck. I've also almost milled myself twice. Against other non-throw decks Omar hits hard because he can block at least 1 or 2 attacks with a character card then trigger mishima family bloodline to draw more cards to block hopefully. I wish I had more kazuymas. Being able to discard a character card for either, a damage pump for merciless fighter, or for Omar's ability has been great. No card is off limit when I discard a character card. Momentum is not an issue at all. Being able to pull cards from my momentum using Body of Souls has been killer to get big attacks back. Hilde test deck just beats up Omar so bad. Its more a speed issue then anything else.