How do you price a membership so members actually see the value?

Straight question, no dressing it up. I run a retainer consulting practice here in Singapore, small team now, and I'm trying to productise what I know into an association membership instead of one-off engagements. We built the tiered structure, we onboarded about forty members in the first push, and most of them renew but almost nobody upgrades or buys the add-ons. So the revenue line is flat and I can't tell if the problem is the price, the offer, or that I'm selling value people don't feel until months in. What have you actually done that moved the needle on this? Not theory — I've read the theory.