What you might consider is "one shots".....
Do you guys have them?.... couldn't be easier. You can even get one shots of many of the top UK liquids.
In truth, if you can do a single flavor mix (I write sfm on the bottle) you may as well do 2 flavors, it really, really, really helps.
There are huge amounts of sfms on e-liquid recipes, most a dreadful beyond my/your worst fear.