I really like Jurica’s idea of the Illusionary Army thing! I always liked the idea of a skill that created huge army of clones. Maybe instead of all 10 shattering the target which would seem Overpowered to some degree (in my mind). Why not like, have 5 clones appear all around your mesmer, and each one will shatter over 5 seconds providing a good heal for each one. Maybe each clone would give a substantial heal, as it would balance out by enemies being able to destroy the clones before they shatter heal.
Thinking about it, why not like a phantasm healer. It could be a phantasm that heals every couple of seconds just like the regular ones. Maybe it could last like 20 seconds, doing a good kind of heal maybe like 1-3k every 5 seconds maybe and then at the end it shatters and heals like 10k, which is good because enemies could destroy it before it reaches that stage so 10k would be nice and maybe heal others.
It would definitely seem cool to have a clone heal yourself hehe lol and of course a skill where you have like 10 clones around you would be awesome! even if it was just for show, like having 10 clones poof around the mesmer and do a big AoE and then disappear, it would still be fun!