I'm building a site to deliver video training courses. There are currently three available courses + an option to buy them all at a discounted price. Other than having the video courses ready to go, I am right at the beginning and keen to get the right plugins in place. When users join the site, I want to offer them a free membership to get them using the site - they will get some free video training included. I want to allow them to create their own user profile. And within all of this to have content & courses unlocked through specific purchases. Which WPMUDEV plugins would you recommend that I use?