I intend to hit 15 before my Gunner weapons expire, and I'll do the next week of leveling my National Soldier to hit 14 so I can at least have Lv5 Combat Medicine and Lv1 of everything but Grenade Spam, which does dreadful damage since the Coastal Clash update (back in the day, Grenade Spam did ridiculous damage since of a so called 'bug'. Soldiers could be downed in one hit of Lv5 versions).