Layout help please

[miggi]

Hi, I'm trying to set up my 4 ft tank to a high standard of planted tank. The slight prob i have is I bought the tank with fish in already so am starting kind of half way through lol. I do not have another tank to be able to put them in while i fiddle so am trying to work out in advance exactly what i want so i cause as little fuss as poss. I am restarting this hobby after a long absence, but when i had a tank b4 i used to buy whatever plants looked decent at the time and stick them into the gravel, fine for a while but they slowly died and were replaced with more. I would love to be able to set up a tank so the plants could GROW and be 'happy'. i really want a tank to be proud of. not just bung stuff in it. I have two smaller filters rather than a large one - i heard this was better for the plants. I have only a fairly thin layer of gravel at the minute, but was thinking of piling it up either end as a terrace and putting silcone sand in the middle. What do u think? i need to create caves because i want to get a couple of dwarf cichids at some point. Is there a type of plant that loves sand? or gets on in gravel better?what can i do? I do have a light so thats not a prob. Ask if you need more info!
Oh and when u buy a plant in a pot do you take as much of the stuff from its roots off as poss, or leave it on and plant it as it is?
Thanks for any help you can give.
Miggi