The phrase "abilities as a" is correct and usable in written English.
Generally, you would use it to discuss someone's skills in a certain area. For example, "Tom has remarkable abilities as a negotiator."
Mentions his abilities as a church organist.
No one doubts his abilities as a coach.
It was, the article added, "the first display of China's abilities as a great power".
Nelson claims he never doubted his own abilities as a singer.
It helped me enormously by giving me great confidence in my abilities as a writer.
I really respect St-Pierre and his abilities as a fighter and athlete.
"I can't believe that people would doubt his abilities as a goalkeeper".
His abilities as a lawyer are depicted as contributing to his oratorical skill to win arguments.
Many other people heralded her abilities as a "connector," including Kenneth Lerer.
Six months into Hillary's undeclared candidacy, doubts persist about her abilities as a political campaigner.
Mr. Watters implied that the deal killer was Ms. Davis's abilities as a speaker.
