Excellent advice from @spikeyxxx and @silentheart00 👌
Is there a general recipe for avoiding too much geometry?
Like silentheart suggested, I usually stick to 10px relative detail size for very basic block out. Then go to 7px for medium details and 3-5 px for the finest details. Often this means I use 10 px maybe 20% of the time, 7px 70% of the time and 3-5 pixels 10% of the time or less. Of course these values are based on relative detail size which is the default in Blender’s sculpt mode. As you get more comfortable you may try the other detail size modes and prefer them which will require their own unique values.
But as you’re discovering the process is not linear or simple. There’s a lot of different factors that will affect your polygon count. As you continue sculpting your eye will start to care less about the polygonal faceting on the sculpture; in fact you might even find yourself preferring it for sculpting after a while. It’s definitely annoying at the beginning – a big detachment from clay sculpting. But I’ve learned to prefer it because it’s like a pulse on the polycount: If I stop seeing facets then I’m probably going to heavy with poly count (too small a detail size).
In the end the digital sculpting workflow involves consistent maintenance. But the more you do it the more comfortable and natural the process will be, including avoiding pitfalls.
PS: Your sculpt is turning out well btw!