Thus, orphans rate, expressed with theese variables: 1 - e^(-x*t0). We see, in first approximation it doesn't depend on T. Dependacy on T arises from network delays.
I agree, that working on payment channels is important. But may be it would be beneficial for Bitcoin to adopt shorter block times. At least it definitely would eliminate that marketing issue.
+1
Sure it would be "beneficial" to lower it to the "optimal" value, but practically speaking it's probably just cosmetic. If the problem is people misunderstanding the issue, then perhaps educating people is the better solution.
We could always do both: try to build consensus for shortening Bitcoin's block time, and educate people on the real advantages and disadvantages of a shorter block time, to dispel the hype about it.
One thing that I'd suggest be kept in mind is that some things are intrinsically easy to market and hype, and a shorter block time might be one of them, so even if the advantages are cosmetic, it would still benefit Bitcoin to adopt it.