This is clearly the most important issue we are facing now. Not spending is equally dangerous. There is no safe way when all the world can copy and outdo us. Fortunately we have DNS, Music, Play, etc. that can all help each other experiment and find what works. However, there are so many trajectories and possibilities, both for getting capital and for spending it, that it may be best to focus on the most robotic and least complex options.
Suggestion out of a hat: something like 6% inflation, with 2% to delegates, 2% to referral campaign, and 2% to interest rate. This would give 1 million dollars for referrals (10$ per signup, 100 000 new users), 10 000 dollars to each Delegate per year (enough to get excited), and +4% interest on every bitAsset. Then we could still brag that we have lower inflation than Bitcoin, and we could use devfund to increase cash for referrals etc., which would increase shareholder confidence that it will work.
I would also like to note that Ripple/NXT was completely outrageous and at odds with the chatter in the whole crypto community at the time they launched, and their market cap rose happily in spite of it - smart money is smart, chatter is not.