I am in the process of setting up a tank also. It will be fully planted and pretty much no-expense spared... The reason I am doing it the "expensive" way, is because my current 2ft has, over the years, chewed up easily as much as what I will be spending on the new one. The point being, it is best to buy the very best that you are able to afford, and not go ahead with this bit or that thing, "just for now". You will most certainly end up spending double what you have to.
Now, having said that, yes, SOME canister filters can be expensive, but if you want a nice display tank, with awesome filtration, they almost cannot be beaten. There are plenty of brands around that will do a perfectly fine job, for not too much outlay. Hang on filters are also good, and not overly conspicuous. These are always available very cheaply. Now, if you are not too concerned about appearence inside the tank, a sponge filter is a great, cheap way to bio-filter your tank. Easy to clean, as well. As to the others...a wet/dry is a great filtration system, but can be bulky and messy. Good for multiple tanks on the same system, though. Internal filters...well, they are just internal filters...they do the job well, but will never look attractive. UG filters are good, but very hard to keep clean...and very 20th Century, lol.
Substrate. Again, find the best you can afford. A gravel of about 2mm grain size is perfect for almost any application, whether planted or otherwise. Of the specialist planted substrates, you could try EcoComplete or Seachem Flourite. These are both around $50 a bag and a far cry from some of the ADA gear that is vastly overpriced in this country. You are right, bright colours are a no-no...not only does bright blue gravel look ridiculous, it does nothing for your fish. Everytime I see a tank with yellow/blue/green/anything but brown gravel, I seriously want to vomit...it just looks naff.
Now, the tank I mentioned setting up, is a long term process. I am buying things as I can afford them. I am not by any means rich, but by doing the research, I have came to a setup that will be exactly what I want in every way. Key point, be patient. Don't rush it. Do what you can, as you can and make sure it cycles properly...
Good luck!