for the people that will actually invest will make little difference, but i don't really know how they are really working this marketing stuff, so maybe they will be effective
The referrer could give his friend half of the tokens back, for example. That could motivate some people to invest. Affiliate marketing is very common on the Internet but pretty new to the ICO world.
And... I'm not that pro for this kind of rewarding, because a lot of bigger whales will gain profit on this... some whales are part of groups that make large investments, grabbing a lot of affiliate bonusses and then they leave the project, causing it to dump fast... I'm more a fan of investment bonusses... this way you only get the reward when you actualy invest own money in it.
If you invested in a project, you already stated you believe in it and you trust it to return a good revenue on investment.
Whales always can make big wins, that has always been the case, where money is, will be mor money.
There is already a great reputation for Sphere, and an excellent community to test your platform, but you really do need to always scale the numbers up and spread your word even more. The Program is attractive and effective, congratulations