Vapers just starting out with starter kits, or egos and clearos, are usually not that fussy about the ohms of their coil, or the airhole size, because they don't know much about it yet. They are just trying to get into vaping. Their gear usually doesn't deliver the flavour or vapor production of a Reo/RM2 combo, so anything that works considerably better than what they have would be welcome. I would be inclined to go just a bit hotter than their existing setup, say 1.6 or 1.7 ohms. 30g on 1/16" drill bit, 8 turns, (and is what I still use). Remember the Ego batts are usually set at 3.6V output so the Reo's going to deliver a bit more than that to whatever ohm coil they were using before. Plus the microcoil adds to the efficiency, and the RM2 gives heaps better flavour. I'd keep it simple, give them the 1.7 ohm coil, and ask them to come back and see you if it doesn't do what they want it to. If they come back you can ask more questions to see what they want. The risk is overloading them with info and choices at the start. Instead you could just show them how to drive it, and send them on their merry way. Usually the first puff where they see a heap of vapor released puts a smile on their faceYou are doing these people a great service, I hope they appreciate it.
Because I WAS one of those people only about 4 months ago, I can still remember what it was like. If someone asked me what ohms coil do you want on your Reo, I would reply with "do you speak English?"
Some spot on advice. One of the guys said it wasn't quite doing it...I asked about his juice. He answered "its medium". I'm trying to save them from going back to cigs, or for chasing the vape they won't find without a reo. If I had an RM2 and a reo early on...I'd have saved a lot of frustration and money. I know I am not alone from reading here.