@boomzilla said:
Your description sounds a lot like US currency, actually, so it's not clear what you don't like, aside from maybe just exhibiting your xenophobia.
I should probably have said "prefer" rather than "like"; my bad.
a) Coinage denominations are more closely spaced, meaning fewer coins required to make change. (Note that the 2p and 50p coins circulate in roughly similar amounts to the other coins. I think moving the 2.5 gap to 20-50 rather than 10-25 makes the smaller denomination coins easier to spend. Certainly I've never needed to use a Coinstar in 24 years of living in the UK; one month in the US on the other hand has given me enough loose change that I do now need to use one.)
b) Coinage is more easily identified due to differences in size, colouring, and shape.
c) Coinage extends to higher denominations (even numerically, without accounting for the exchange rate), so:
i) Vending machines needn't accept notes in most cases, reducing cost of construction and avoiding having the machine reject your perfectly valid notes because they're somewhat tattered
ii) You can reach into a pocket and pull out change to pay for most small purchases, rather than grasping at a pile of folded bills and trying to work out which ones are the ones you need.
d) The points you raise about your notes. Our notes vary in size (although only a little, not enough to make huge problems for wallet or self-checkout manufacturers; see point ci regarding vending machines, and I would presume that the different sizes could also be used to confirm denomination in the latter case). They are also distinctively different colours (I can now sometimes identify a $5 bill based on its colour; the others I'm still stumped by)
e) An entirely aesthetic complaint – the plating on the coinage makes them look either forged, dirty, or like there is a second coin present in a different denomination.
So there are some things I prefer about the UK coinage that aren't (I don't think) xenophobically-motivated. I still can't think of anything I particularly like about the US circulating currency (in preference to the UK's). I have fewer objections to the circulating Euro, although the intermediate-value coins are again similarly-shaped and coloured making them similarly difficult to identify to the US coins. At least their sizes are consistent, though (increasing size = increasing value). I haven't had much experience with any other currencies, so can't really provide any other comparisons on the xenophobia front.