Depends on how much you love plants.
With a good bed of substrate and good lights you can fill the tank up with real plants. If you want a designer planted aquarium with a "lawn" and stuff, then it gets pretty complicated and you'll need to inject C02 and dose certain fertilizers and trim the plants in a certain way, etc.
The plants I've had best luck with are Amazon Swords and Giant Vals. They're hardy, don't need C02 injection, and grow and spread quickly.
I've had 2 planted tanks with good results. They each have about 2 watts of LEDs per gallon of water, and 2"+ of planted substrate - the kind you can buy at Petco or Petsmart. No C02, no fertilizers. The plants are great for aquariums - they help filter the water like activated charcoal, they prevent algae, fish like them, and they will always look better than fake plants.
Plants LOVE fish poop, its natural fertilizer. With good substrate and a fully planted tank you don't have to clean the substrate at all, the poop and debris sinks into the substrate and is eventually "eaten" by the plants.
The downsides to planted aquariums is if a plant dies, you should take it out so it doesn't rot. You'll want a "clean up crew" - some Bristlenose plecos, amano shrimp, snails, etc. Not always practical in a "monster" tank. Also, larger fish uprooting plants can be a pain, although plants like Amazon Swords and Giant Vals have pretty deep root systems and aren't easily uprooted. If your lights fail all your plants will die which will also probably kill the fish, so you have to make sure your lights are consistent. Overall, I really like planted aquariums (obviously).
These are the 2 planted tanks I've had with good success.
This is probably my favorite planted "monster" tank, 185g silver dollar tank (not mine)
