It makes no sense that only LTM's can become referrers imo. So we should change it if possible.
We want everybody who uses BitShares to be able to give a link to their friends, family and colleagues and if they sign up they get the referral income. No need to understand/pay for anything.
Open a BitShares account, share this link, earn money.
Look at the Coinbase referral programme as an example..
https://support.coinbase.com/customer/portal/articles/683805-how-does-the-coinbase-referral-program-work-They don't expect you to pay money to become a referrer, that would severely limit it's use & success.
What's also interesting is that the Coinbase referral programme started at $25, then trialled $75 and is now down to $10.
This shows that changing the initial parameters isn't the end of the world and that while a referral programme is a great marketing tool,
sometimes less is more in terms of balancing cost to Coinbase and the returns.