It certainly gets colourful, doesn't it!
Believe it
My only real mistake was buying some Spanish National Team bibshorts, I just couldn't resist the price but read and white bib shorts on a fat bloke don't really do it, they're reserved for training now.
Layering, or lack thereof, is really up to you and how you ride, there's a rsik with going too minimal for a big bloke. It's temptig due to the overheating going uphill etc but it doesn't half get cold on the downhill. I'd just try a few things and see how it pans out, if it helps this is what I tend to use:-
hands - I have cheapo Winter gloves from Aldi or Lidl about £5 per pair, mitts I use fingerless ones with minimal padding as I have heavily padded bars. I also bought some pairs of silk liner gloves from e-bay
http://shop.ebay.co.uk/jasminesilkdream/m.html?_nkw=&_armrs=1&_from=&_ipg=&_trksid=p3686 I find these wear well and can be used under mitts or Winter gloves. If it's really cold then you can wear these, plus nitrile gloves, plus Winter gloves, your hands will sweat but they won't get cold. I found these were perfect with the mitts on a cold start and allowed me to remove a layer when desired.
feet - I use flat pedals so can wear what I want and do, everything from heavy boots with extra socks right down to flip flops(they won't be repeated) though I now consider crocs/sandals the minimum.
bottoms - I have some padded boxers if I want to ride in normal trousers or shorts, don't really like cycling in jeans over about 5 miles and wet denim is no fun. For commuting and longer rides then it's generally lycra, bib shorts or 3/4's, leg warmers, leggings - mix it up as it works for you
top - windchill is the bit to watch for here and I have 3 options,
Altura Nightvision, Montane Featherlight and Montane Feartherlight Gilet(sleeveless jacket), I also like micro fleeces, Craghoppers do some decent ones cut long at back. I nearly always wear a base layer, under the bib shorts, and mine are all merino wool ones. I don't like a lot of the cycling tops, even when slim I just don't like the material and, no matter how much you spend, the anti smelly treatments don't always work or last. Again I'd go for merino wool, costs more but feels nicer to me and doesn't get stinky. I'd rather overheat a bit than get too cold, I had some early commutes where I was under dressed, it was miserable.
To be honest I quite fancy some cycling specific 3/4s and trousers, for social riding, but don't really want to shell out until I hit a reasonable weight again. Partly coz they won't fit for long and also they tend to consider XL being a 36" waist. The Montanes are great coz, like the silk glove liners, they pack really small so can be a layer you carry all the time. It has to be really cold for the Altura but it's nice to have something along that you can whack on if the windchill gets you by surprise. A buff is another handy thing to carry can work well to take a bit of chill off or to mop up sweat.
and look in reasonable condition. There's nothing like buying new stuff to get you a bit more motivated and enthused.
Still nothing like a challenge eh?
