I am not an expert on ninja, but I'll share the stuff I learnt so far;
- the difference btwn kagerou and oboro is that each of them have a little advantage over the other, kagerou is more pvp oriented and oboro is magic oriented based on their individual job skill
If you want to know about what skill you should have and what weapon you should aim for, refer to this this thread ; here
About your hybrid: I can see you are trying to make kunai magic, so I think you need to lower your 16th Night skill to lvl 3, get some Illusion Shadow skill for protection, and get some Oboro skill if you want and most importantly put some more points into Flaming Petal and Freezing Spear until at least lvl 8.
In case you didn't know, Wind Blade is not spammable like FP and FS when used with 16th Night skill due to its longer after cast delay.
Stat suggestion: 100 str, 100 dex, 100 int, 100 vit and the rest up to you
I dont have experience about melee/KS kagerou, but I'll give my opinion a bit.
- if you plan to use Killing Strike a lot, make sure your Mirror Image is lvl 10 as it maximize the damage.
- maximize Dagger Throwing Practice is you want to maximize shuriken/Huuma Shuriken damage
- getting a Pure Soul is a MUST for K/O. But no idea what 16th Night is good for melee K/O tho
- get Earth Charm skill as it increases your physical damage
- about those pvp skill and kagerou skill, I have no experience about it except for Shadow Warrior skill. This skill give your K/O ability to do Double Attack like thief/Rogue/DA sin. This skill is a BAD joke for a lvl 100+ char, so dont get it. EVER. You wont kill MVPs ctrl-clicking with Shadow Warrior on.
As for Rapid Throw, I've never seen it in action as I never go pvp with my kagerou. But from what I read so far, this skill can do crazy damage and you do not need a brain to use this skill, you just need a lots n lots of zeny$$$. If you have fukktons of zeny, maybe you should try it lol.