In winter, I struggle to get above 30% RH even with a humidifier and my air conditioner keeps my VPD within a reasonable range the rest of the time. IMO for small scale home grows, I think fussing with tight VPD control is just a lot of expense and work. It's bad enough I have to PH every drop of water/solution that I use. Micro-managing my grow takes the fun out of it for me. KISS has been my guiding principle and has served me well.