My smaller YM "time frame" chart is a 250 ticks. From 9:30 to 4pm Est, it takes between 2 seconds and 3 minutes to form a new candle. I think it is much easier to feel the momentum of the market. Regarding the smaller time frames, you would probably need to have smaller stop and limit sizes per trade, and then the % of the costs will be higher (fees, commissions, slippage, etc.). This is why day trading is harder: The odds are clearly against us.
As I'm UK based, and because most people viewing this thread are trading ETFs in the US or elsewhere, I think this is probably not the right forum for me to be posting on, so I'm moving elsewhere. Anyone who wants to follow me, throw me a pm and I'll respond. All the best, Slepoy.