Retail Park would be a disaster, it can take me an hour to get from one side of town to the other after my work, either way out of two. The set up of town is an absolute shitemare with traffic. McDiarmid gets you on the bypass almost instantly. Thanks for proving my point though, folk still moan about McDiarmids position, yet we're perfectly fine and managed to gain fans.
St Johnstone attendances are higher than in the 70s/80s, there was a huge upsurge after the move, along with most clubs at that time, so don't get distracted by that.