Hi Steven - yes great question!!!

I always recommend drilling scales in your practice routine because it's important for guitarists to keep working on your basic picking mechanics - strength, dexterity, and sense of timing - just like an athelete runs drills over and over in practice. Work with a metronome and the process is easily trackable -- you always want 5 or 10 minutes of repetition, running through your scales, at a tempo where you are executing everything perfectly. Always try and bump up the tempo and see if you can increase the bpm over time - this builds your overall speed, dexterity, and timing!

That said, of course, working through songs is also incredibly helpful - so yes, continue to do so! Just remember when you encounter difficult material to isolate the phrase/riff, slow it way down, make sure you learn how to play it correctly at the slow speed, then repeat, repeat, repeat to program it all into your hands and fingers!

Hope this helps! Let me know how it's going!

Mike