This guy is very well drawn but I feel I should point out that the extra sickle claw on a Balaur's foot was formed by the hallux (the innermost toe), so Balaur still had the same number of digits on its feet as other dromaeosaur species. It also likely had a full coat of feathers.
Ah I see, didn't catch that you were basing it on a OC design. As far as the feet go, don't worry you aren't the first to accidentily give Balaur extra toes.
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"Well excuse me for having enormous flaws that I don't work on!"--Homer Simpson