Taste: composed leads, thought out, and always mirror the feel of the song.
Emotion and intensity: many of Skid Rows most famous songs were sad, minor-feel, heavy ballads, and he played his ass of in these, his best solo is in the song Wasted Time, where he plays a fantastic solo, filled with intese bends, vibrato and phrasing, and build a crescendo to an intense ending.
Chops: he could blaze away quite fast with very good prescion.
Songwriting: in Skid Row, writing is mostly done by the parternship of Sabo-Bolan, Scotti's work was to lay most of the solos.
Distinctiveness: tough he's an intresting player, fairly choppy, emotional, tasty and intense, he brings nothing new to the table, and when his band rose to fame, he couldnt show anything to set him apart from the dozens (maybe hundreds) of metal players in the late 80s.
Also, in Skid Row, the spotlight was always on lead singer Sebastian Bach, because of his amazing voice, and range, and his energetic stage-persona, he was always the center of attention, and while Bach was probably the strongest element of the band he also took the attention away from the other members, and Scotti`s playing was overlooked because of this.
Rythym-wise, Skid Row employed some intresting clean parts in many songs, with chord progressions that are more complex than the rock basics (Wasted Time), also you get some cool arrangments over standard progressions to make them more intresting (In a Darkened Room). You also get some really good, heavy-ass Dino riffs (Piece of me, Youth Gone Wild, Slave to the Grind, Monkey Bussines) . While Scotti doesnt wirte most of the parts, hes able to play them, and they integrate his rythym style. In the Skid Row version of Little Wing, he integrated elements of Hendrix palying with his own style, and also does a personal take of the solo.
Scotti is the main lead guitar player in Skid Row, and as his not a songwriter, this is where he gets to express himself best. He plays a lot of aeolian minor, blues scale, and some major pentatonic. He might explore some other scales from time to time, or insert some chromatics in his solos, but most of the time he stays in the mentioned scales. He uses wide bends, agressive vibrato, pinched harmonics and whammy tricks to achieve intenstity in his playing. His aproach to soling is mainly combine melodic pharasing with aggresive attitude and fast runs and fast repetitive licks.