While you dont need live plants, they are a huge asset to any tank. They are a soft and natural place for your fish to hide and sleep on, as well as a great way to remove ammonia (stemmed plants work best for this). If you want to get a plant, go for it! I made a thread on easy care plants, if youd like to look at it. Find one that works best for you- one that you can care for based on your substrate, tank size and lighting :)
Most bettas do not care for current. While yes, there are exceptions, bettas generally do not like to have to contend with a strong current or one that disrupts the surface. Waves on the surface make breathing from the top harder and with such large fins (on males), strong currents from filters and bubblers means more work to swim around and more energy to waste.
You dont* need a bubbler or a filter for your tank, since bettas breathe air from the surface. If you like the bubbler and it doesnt knock your fish around or make the surface wavy, its probably just fine. If not, try lowering the power or dock the power if it uses airline tubing by sinching it. At a lower power (less bubbles), my fish enjoy playing and biting the bubbles. I do not leave it on all the time, maybe just for a few hours.