I get a bit confused with the naming schemes different companies use. IKEv2 and L2TP both use IPsec so is the 3rd option "IPsec" IKEv1? Anyway...
On the edgerouter most people use L2TP for this kind of application. It's been around for a while and is fairly well-documented including a help article:
https://help.ubnt.com/hc/en-us/articles/204950294-EdgeMAX-L2TP-Server
If you are feeling adventureous (It doesn't really sound like it though) you can try IKEv2. There is a thread about it here but there is a bit of work to get it going
I believe IKEv2 is better at handling clients who change IPs frequently (cell phones), and has less overhead.