IMO it wouldn't be the best CPU for gaming- specially for R3E. I'd prefer the I5 6600K, which has much more power for just 20€ more. Is there a special reason you've selected that CPU?
Even that rather old CPU has a higher clock-speed than the 6600T. Unfortunately that is quite important for R3E. And the higher the level if detail and ammount of opponents the more demanding it gets.. For sure - the low TDP of the 6600T is nice - especially if you plan to go for passive cooling. If it must be something like that I guess there is no alternative.
That 6500t has a very low clock (2,5ghz/3,1 with boost).Better buy an i3 7100 for less money and only 15w more than that i5.Or go for the normal 6500 with a much higher clock.
Meanwhile I bought a Pentium G4560 and undervolted it by 0,1 V. It was much cheaper and is good enough for steady 60 FPS in 1080p.