Deciding on which type of fish you want to keep would be ideal.
That way you would be able to get items you would really need and not waste too much cash.
Cichlids would need a different set up than a Tetra centric planted community tank.
Bubble walls are just for fun, and not needed in a planted tank. One exception would be if it were a fancy Goldfish tank, then having extra aeration would be a plus.
You are solid with a really good filter, though I would go with the fx-6 for such a small amount of money difference new. But if you have it already or had one you are planning on getting then what ever works best for the budget. That is a big tank and all the extra filtration you can get shouldn't be a bad thing.
Filters say they run a certain GPH
-(gallons per hour) but once the filter media is stocked up and then it gets some age in it, and some muck, the number go down quite a bit. I think they run gph
with no media, and brand new, so it gets a better rating. They all rate it that way though.
Again knowing which direction it will go /build for the new resident, will help a lot.
Usually a heater is needed but sometimes you don't really need one in a warmish house if you have Fancy Goldies, but if you have a tank of German Blue Rams you would want a bigger one to make the tank warmer.
Substrate is different too for who goes in it.
A liquid master test kit is a good start! API has a decent one and online they are cheap to buy. Top of the list of things to have.
Container/tub/Tank for quarantine tank aka QT. Air pump, hose and air stone with a check valve is important to have for the QT and as a back up for a damaged filter situation.
What are your water parameters out of the tap? That also might help you decide what to house. Extremes like super hard or soft water can make a big difference in how easy to keep some kinds of fish will be.
Also there is an article link in my signature about being new to aquarium keeping and it is a great help with lots of info!