Tate no Yuusha no Nariagari left me both pleasantly surprised, confused and frustrated all in one go upon finishing it, and for quite a few different reasons which I'll attempt to list below and bring together into something of a review for this, if nothing else, intriguing anime.
(Side note, i'm going to heavily AVOID spoilers as i sincerely think this is an anime worth watching so i won't be addressing any particulars about the show but talking generally. Also I ramble/rant like hell so good luck.)
Firstly I want to say that Shield Hero well deserves it's quick rise to fame. It's first few episodes where absolutely awesome in how it set up the rest of the story. The rejected, bitter angry MC, the quest for both vengeance and justice, redemption and blood... really impressive set up to the story. However, as with many extremely ambitious shows finding the appropriate pacing is extremely challenging, especially when the story and the setting essentially demands characters to have their personality change, and their goals to change. This is extremely hard to pull off and I will be the first to admit that the "transition" period in the middle of the anime was certainly rocky in it's pacing.
However while it did somewhat detract from my overall enjoyment of the show by the time I ended it I was actually quite amazed by how well the storyline stays coherent, progresses AND leads to honest-to-god character development.
This brings me on to one of my main points. Characters. Overall...?
I'm very pleased and here's why.
Rapthalia + Naoufumi's relationship. Full stop.
Honestly the rest of the cast was pretty good, and fulfilled their roles wonderfully. The princess was actually useful and had princess-levels of influence. The other 'heroes' where both wonderfully hate-able and yet surprisingly relatable. (aside from the "Dual Spear" hero...)
However Naoufumi and Raphtalia's interactions were absolutely on point. Watching his personal and moral struggles, his internal battles and how time and time again he strives to be an actual hero, saving lives and sacrificing his own, lead to Raphtalia maturing, and it shows (physically and mentally :P .) Likewise Raphtalia's own pain and vulnerability inspire and spur Naoufumi into even more heroic acts and his reliance on her love and devotion to over come his worst inner demons was sooooooo nice to watch. Some people may be frustrated by the "lack of romance" but I don't think it would have added much in particular to what the writers already managed to develop and the final episode just made me smile at how nicely and honestly they developed/concluded their relationship.
Is this a perfect anime? Hell no. There was so really dumbass fights and ass-pull abilities. Were all the characters amazingly developed? No. Was the pacing steady and intriguing with little to no filler? Not really. HOWEVER
Does it have an actually interesting world setting? Yes. Was the MC both interesting, develop, AND was not a wimp? YES YES YES YES YES. Was the love-interest believable and develop? YES! Did the story progress well and both answer questions, resolve issues, AND reveal even more plot? YES!
As far as existing Isekai anime go, I rate this up there as one of the better ones. It holds it's own among Log Horizon, Fantasy of Ash, and Reincarnated as a Slime.
As a matter of fact, I'd say Reincarnated as a Slime is a decent one to compare with, a standard, boring, repetitive, "hero transported to another world and given crazy powers" anime that has no right to be good yet somehow competently steps into the mold of Isekai and says, "No, no, no Mr. Cellphone-kun... here's how you make a REAL Isekai!"