Improving Referral Virality

You're a growth product manager for a ride-sharing app. The referral feature was launched a quarter ago.

While the quality of customers from referrals is good and similar to other channels, the virality is low (K-factor of 0.05), preventing it from becoming a significant growth channel.

→ Without access to data, what are the top 3 ideas you will try out to increase referral virality among the members?
→ If you are given access to company data, in order to come up with/fine-tune the above ideas, what are the first 3 questions you will seek to answer?

See hint