Pulp day tickets sold out and weekend almost sold out for Tramlines already (tier 5), so no need to hold back - and surely they could have anticipated this would be the case. Tramlines not showing as festival exclusive though, so who knows.
The crowds are my main worry, especially when you have a big crossover like the park and pyramid emptying at the same time. I've had 20 years of getting mangled and not done for a few years now, so that's less of worry to be fair