By saying "Who ever say Itachi has to be high" you don't prove your argument valid in any way,just for starters.And neither helps for a civil debate as you already categorize folks who don't share your subjective opinion.
Now I'll try to breakdown as clearly as possible my point of view on the matter...
1)Sacrifice
Minato was the Hokage,and by that he had to comply with his duty as such,namely protect the village when in danger,readiness to put ones life on the line to save the rest,in other words encompass the "Will of Fire".So what Minato did is not something that hasn't happened before his time or that didn't happen after,as it was his duty to protect the village.And with all those responsibilities,came also benefits such has fame,"acknowledgement" of the efforts,and a giant statue that carved his name in the book of history.With this in mind I deem his sacrifice as something very positive but nevertheless not unique.He sacrificed his son and his wife of his personal belongings and therefore saved the village.
Itachi wasn't Hokage,and wasn't burdened by the responsibilities of been one so he could have simply chose the easy route in life,and do what pleased him the most.But he didn't as we know full well,he with his own hands decided to slaughter his bretherens,lover,mother and father because he had knowledge of events greater than himself,but still with all those burdens bestowed upon him he never showed distress,he always maintained his "Illusion" of been "borderline insane".Itachi was a living Izanagi as he appeared to the rest of the world invincible but ironically knew full well that manipulating his personal state of existence was going to inevitably lead him to his death.As the very words of chapter 400 ring clear in my mind as it if I read it yesterday when someone as amoral as Tobi said he couldn't fathom what thought processes must have been going trough Itachi's mind during the clan massacre.Just think of the fact tha he could have been the strongest Uchia of he was egotistical or that he could have become a well renown shinobi in the world,or simply loved by those around him,but no he swallowed his emotions in blood and tears and decided to do what what rightand not what was easy.
So for the sacrifice I give it definitely to Itachi
2)Plan success/consistency
Minato on that fated night was faced with an evil too great for him to handle it single handedly,so he decided to Hope in the future and entrust his son own son with a power capable of defeating such evil.Now this plan isn't technically speaking much consistent as it was all placed on hope,hope that his son would stay in the right path,and someday learn to harness such great powers.But the key element in the plan was all Hope and some luck,but sure he did take some safety measures in the form of Gerotora(the key frog) and him appearing in the subconscious of Naruto.So the consistency of the plan was,to put it in numbers 4/10.But as we all know his plan will definitely come to success as his son his the main character so definitely when the show ends his plan would have succeeded entirely.
Itachi still wasn't faced with Immediate evil,but sure for this his burden wasn't in the slightest lighter,as the worst case scenario was a full blown shinobi world war.Needless to say like Minato's flaw was entrusting everything on a new born baby,Itachi's flaw was not killing Sasuke,as the latter was his form of Hopeon a brighter future for his beloved clan and more than anything his beloved future.His plan unlike Minato's had more safe measures and was relying not on luck but on certainties,namely the Kotoamatsukami on Naruto was 100% plan success,or the Amaterasu on Tobi,or even the entrusting of his powers to his brothers,so he would become stronger to some day challenge "The invincible Madara".The consistency of his plan to put it in numbers was 8/10 as it relied too on hope which depends on luck to some extents but indeed had more safety measures.As for the success of his plan until this very moment has failed,and his plan unlike Minato's isn't related to the main character so it doesn't have assurances that it will come to fruition.
So the Plan success I give it to Minato,but the plans consistency to Itachi.
Don't jump on my throat for the long wall of text but hey,at times I get carried away,especially when it comes to 2 characters I'm interested in.