The mackies will almost certainly be WAAAAYYYY too loud for your use if you wind `em up, but at least you would have a nice lot of headroom.
Yes, the 450s can get very loud, especially in a small venue. However, all you'll get is a harsh, painful mess of 2-8kHz and not much else. The 1521s I suggested aren't quite as bad as the 450s in this respect, but you'll still need to cut that HF area quite a bit to achieve satisfactory results.
It sounds like the original poster would like a high quality, full-range sound. Good for a full mix including drums etc. I would say that subs will be required to fulfil this requirement. The idea is to run a speaker system well within it's limits. If you start to push a system to it's limits then the result will sound horrible. You may also cause unnecessary damage to the your ears.
By the way Mackie BOUGHT RCF speakers in order to develop their speaker range, so choosing between Mackie and RCF is not necessarily choosing two different things!
It is true that some speakers in the Mackie/RCF range are identical. However some are not. Did you look at the speakers I suggested? Mackie does not offer anything like these.