Character archetypes are pure shonen
Lost comparison was only due to Lost sucking you in with cliffhangers, so the audience often didn't let the episodes stand on their own and looked forward to what would happen on the next episode. Not necessarily a bad thing,but yea I agree Lost didn't know what the hell it was doing.
Archetypes and common personalities is not what makes shonen shonen though. Its got a squad, yeah, but its not very much like the typical stuff out when it comes main character powering through all odds with the power of friendship or something. Maybe the power of PTSD here, but I'm pretty sure that doesn't count. The fanservice is also pretty low on the scale as well.
Also, Lost fucking sucked and everyone who watched it over Battlestar Gallactica has a 99% chance of being a lame inside and out.