I ain't tryin to be a fanboy or anything.....but Tobirama is pretty well rounded.
-Senju chakra and stamina
-Mastery of water style
-Edo Tensei
-S/T ninjutsu
-Sensor
-Pretty good taijutsu and genjutsu if you count the anime
-Intelligence
In an interview, Kishi said that Tobirama was more suited to using the bringer of darkness tech than Hashirama
The thing about his S/T technique and Edo Tensei is that he created both of those, thus showing off his high level of intelligence. I've noticed the correlations between Minato and Tobirama. Though, Minato doesn't have a mastery in a certain chakra nature.
Kinda funny how they both sensed 20 opponents using that technique.. I sense a parallel >_>
OT: Edo Tensei is pretty haxed. Can basically revive all the great ninja of the past.. plus if you have some form of "immortality" (cue Orochimaru and possible Kabuto), then you're not as limited by a natural lifespan IIRC.
the most complete and best ninja would have to be kakashi. he has the most well rounded arsenal, with perhaps the best analytical skill in the world. being powerful just makes you arrogant and overconfident. kakashi can see a situation and read it with the best course of action, no ego involved. and hes good with the sharingan which isnt even his to begin with. sometimes people are sloppy with borrowed power like kabuto's ETs.
second is kabuto since he can have his summons do all the fighting, making him the best ninja in terms of acting like an actual ninja. sneaking around in the shadows, gathering info and graverobbing. thats a real ninja. and his summons happen to be the most godly ninjas of the past.