I think that what you wrote about TRON is right. What is scary is that a "project" like TRON (some would call it a scam), can rise to a few billions worth of value in a very short period of time in the crypto-sphere.

I think everyone has the same questions about XRP. I do think they have a real technology. I don't like that it's centralized (running counter to the whole heart of cryptos). I don't see a way they can "pump" their coins value, but everyone's fear is of them diluting its value. However, they have apparently placed the remainder of the XRP they own in an escrow account.
All good measures. I'm invested in XRP (since $0.18) and do believe that the tech vision is there, not to mention the size of the market they want to service.