Sleek's powder blushers are very pigmented so be very careful and light-handed when applying. I really like the Blush by 3 palettes.
Mac make very nice powder blushers - they generally aren't so pigmented that they are hard to apply and they last really well on me.
I usually match my lipstick and blusher so they have the same tones.
If I only had one blusher, I'd go for one in the same colour as my cheeks when naturally blushing.
I'm quite fair (Mac NC15-NC20) with warm/yellow undertones and I don't think that peachy/orange tones suit me. They blend in well with the warm undertones but they don't look natural IMO - I don't blush in orange tones so I rarely wear those colours on my cheeks.
I like wearing Mac Quite Frankly Scarlet, Chanel Ultra Rose (this is a bit lighter and more shimmery than the pink colour in the Sleek Pink Sprint palette), Mac Bite of an Apple (reminds me of one of the colours in the Sleek Lace Blush by 3 palette) and Mac Prom Princess (this is similar to one of the berry colours in the Sleek Pink Sprint palette)
Chanel's blushers (both cream and powder) are lovely. For liquid blusher, I like Daniel Sandler.
For the powder blushers, I'd suggest a Real Techniques Blush Brush or a Mac 167 or 168. For creams and liquid, I'd go for a stippling brush (Mac 130 and Real Techniques have one too) - with creams you can use fingers if you prefer.
If you do apply too much blusher, you can tone it down a bit with your foundation brush.