I would skip the heater just because none of the plants need it unless you house is getting into the low 60s. Even then they will all live but might not grow as fast. You are definitely going to need fertilizer and a light source.
If I were to spend my money on any two things other than the tank itself, it would be the lights and substrate. Spend the money to get a clip on planted tank light or a finnex (something cheap and doesn't need to be powerful). For the substrate, get a purpose made planted tank substrate and it will save you more hassle than you knew was possible. Other than that the sponge filter and air pump would be helpful for more aeration. In terms of plants, I would stick to the things you mentioned and beginner stem plants. Ask the person you buy them from if they are good for beginners and low tech substrates. I like stem plants because they are a lot of fun to collect and propagate.Good luck
