The Apilus Junior I’ve seen do operate in blend. If you look at the 3 buttons along the right side of the control panel the top one is for thermolysis the middle button for blend. You adjust the amount of the current and the timing for each of the 2 currents by pressing the corresponding buttons on the top just under the display and using the + and - keys. Pretty simple machine really. You’ll want to do a bubble test and an egg white test before you use the machine on yourself to make sure everything is working properly.
For DIY optics, if you are working on a body part you can get a circle magnifier off amazon cheap enough, look for about 5X magnification . For facial work, nothing really works except a magnifying mirror, and I have some 12X magnifying mirrors for this purpose.The rest, is pretty much all ergonomics of working.