Audiences put a large value on big voices so its easy to understand why singers are prone to overworking. While strength and control are always welcome, working loudly and muscularly are the wrong way to get there. The calm and relaxation of the face and all the muscles involved is key to complete resonance, so singing small is actually the fast track in strength training. I know this, and I alway start my prework (warm-up) small, but the other day I started singing a new song and realized I need to incorporate more small complete resonance in my performances.
Not, airy, not breathy, just small. A small and complete ring like the vowel/ consonant exercises in my lessons. No expansion, no self amplification, just calm, relaxed, complete laryngeal buzz ! Its healthy and feels right. Its like a vocal massage as you pass from pitch to pitch.
Start in a nice low key and enjoy the simplicity.