It's perhaps understandable that there might be bigger than usual crowds while they try to make it a "big thing" in itself.
(To be honest, I'm genuinely surprised at the slightly over-egged amount of publicity that the council managed to spin for an area little bigger or longer-lasting than the average demo or parade through town («waves at PoP pandas»), but all to the good for when it gets properly bigger and better.)
I'm not so sure that, in the long term, they should really try to organise a large number of activities, but more let things just happen more organically/naturally, and then there will be less crowding and more of an experience of people getting to enjoy the city centre as part of normal life (which means less pressure and less potential conflict between people walking and people cycling too).
(It would still be good if folk could counter the anti-cycling comments on the council's Facebook page, however.)