I think your piping is very nice. Maybe squish a little harder on the petal one so that it looks fuller, but only a cake decorator would say that, most likely. Your family and friends won't think a thing about it. The yellow is a nice color. I don't like the pink at all...wouldn't like it by itself, and certainly think it's out of place with the yellow. But, I think by your original post that you already knew that. You were just looking for validation of your gut reaction...right? 
I'd look for a softer, more toned-down pink for future use. But, other than that, you're doing just fine.
Also, I was going for a lighter pink but got too much dye in it!
I think I would ice the cupcake the same color as the petals on the flower were going to be, so that the whole top of the cupcake becomes the flower...kind of like how I have seen people do a big rose for the top of a cupcake. I would have the petals sort of hang over the sides a bit or something like that, and since its the same color as the petals you wouldnt notice if say one part had a thin petal or leaf......if you wanted to add any green I would say maybe just a leaf or two around the outside....very cool idea though...
http://www.cakecentral.com/modules.php?name=coppermine&file=displayimage&meta=search&search=cupcake%20rose&cat=0&pos=6&search=cupcake%20rose
this was done on mini cupcakes, but it shows kind of what i was talking about.....
http://www.cakecentral.com/modules.php?name=coppermine&file=displayimage&meta=search&search=cupcake%20flowers&cat=0&pos=11&search=cupcake%20flowers
ok last post, but I love these cupcakes boonenati did....just some more ideas (can you tell I just love cupcakes! LOL)......
They're regular sized cupcakes, though. Quote by @%username% on %date%
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