I'd go with a canister filter. I prefer the Fluval line, a 406 would work fine.
Substrate really depends on the look you are going for; natural river pebble, pool filter sand, black sand or a pebble look. Black Diamond blasting sand is good, Eco-Complete is good but pricey, pool filter sand is good and can be found for cheap, river pebble can be found for cheap as well.
It also depends on your stocking. If you want loaches or cory catfish, sand is better because of their barbells.
There's lots of ways to make a cheap gravel into a good planted tank without having to spend the money on something like Eco-Complete or another specific planted tank substrate.
I use pure untreated kitty litter (no clumping agents, no scent) it's usually sold as Oil-Dry (for soaking up spilled oil and such) just make sure there's no additives. Put a layer of that under whatever substrate you choose; pool filter sand, black diamond, river pebble etc. I also mix some Flora Base with mine, but it's not something you have to do. You can mix a very small amount of Osmocote Plus Plant food in the kitty litter. And I do mean a very small amount. I tried this with a tank I just set up recently and so far so good. No algae blooms.