crackerjack

accomplished, ace, adept, complete, consummate, crack, educated, experienced, expert, good, great, master, masterful, masterly, practiced (also practised), proficient, skilled, skillful, versed, veteran, virtuoso

A-OK, A1, awesome, bang-up, banner, beautiful, blue-chip, blue-ribbon, brave, bully, bumper, capital, choice, classic, cool [slang], corking, dandy, divine, dynamite, excellent, fab, fabulous, famous, fantastic, fine, first-class, first-rate, first-string, five-star, four-star, frontline, gilt-edged (or gilt-edge), grand, great, groovy, heavenly, high-class, hot, immense, jim-dandy, lovely, marvelous (or marvellous), mean, neat, nifty, noble, par excellence, peachy, prime, prize, prizewinning, quality, sensational, splendid, stellar, sterling, superb, superior, superlative, supernal, swell, terrific, tip-top, top, top-notch, top-of-the-line, topflight, unsurpassed, wonderful

ace, adept, artist, authority, cognoscente, connoisseur, expert, fiend, geek, guru, hand, hotshot, maestro, master, maven (also mavin), past master, scholar, shark, virtuoso, whiz, wizard

beaut, beauty, corker, dandy, doozy (or doozie), dream, honey, humdinger, jim-dandy, knockout, nifty, peach, pip, pippin, standout