No_Existence
For me the problem wasn't that he went to rezero it was that you did it so early on in the dxd storyline. If you did it later on say around after the riser arc then I wouldn't really have a problem with it.
1. The title has DxD in it. People will come for a DxD fanfic, and hence, that's what they have knowledge on. I'm all good with Re:Zero, but that is because I know the plot behind it. I can see how someone would be upset with Re:Zero cutting off the DxD story before it really got a chance to start, and now they have to read something they know nothing/little about it. A more detailed explanation of the plot/impossibility MC is chasing would go a long way, and perhaps an auxillary chapter would even be a good idea(I know a lot of us are too lazy to look things ups ourselves). 2.) Resets.... this will kill the story if it's just an endless cycle of hard resets. There needs to be some kind of progression. Perhaps have the power systems follow him, or maybe his expierence in multiple systems increases the power of his magic/abilities for each system and any future system he runs across. Kinda like using mana, gates, chakra, reiatsu, nen, etc for demonic, holy, destruction, and trinity magic will let him use it extremely effectively and use it with a huge power boost despite the power system that is used. Then when he learns a new system, his base level is already really high due to all the other systems' training, but he can still train it up to get even stronger based on the potential of the new system. You can also use the impossibility to steadily remove the reset effects until he can carry over all of the power from world to world. You could also pick a main world(like DxD). If there will always be hard Resets, it will be a lot more manageable if he only spends a short amount of time in the new world sparks and then always comes back to the main world where he would have his true body/power.
honestly it just seem too early to go to a different world cus i feel like You build up the suspense and the idea of when his father will find him And then boom different world. just made it a bit of a mood killer you know Which just stop me from reading for a couple chapter releases course I came back because you're a really good story writer just please don't be so abrupt about it next time that's all.
I'll be honest I would have preferred him completing the DxD canon since that is what I came for also the fact that MC is the son of Sirzechs and am Angel plus adoptive son of Freyja and I've gotta feeling it's gonna take a long time to finish it. That's the reason I'm so annoyed with the story I really wanted him to at least meet and talk to Sirzechs and Grayfia. Otherwise the stories great even tho I've never watched rezero I've seen alot if fanfics about it. Oh could I recommend him going to Fairy Tail and getting Erza as a knight, and Mira as a Rook for his peerage please?
this is what i would like the see in the future correct me if Im wrong one of the things hes doing is collecting sparks of impossibility i would like that if and when he hes enough spark and he goes to a world with no magic the fact that sparks makes him a being that is inherently impossible he would be able to use magic
Honestly I enjoy how it is going so far, especially the Nerf he gets when he travels to a new world it will allow for the story to progress and allows for more worlds as you wouldn't send a OP guy over to 'To love Ru' as it would be over kill and make a bland story. Also can we get a monster musume world for waifus.
No problems here. I already knew that this will be a multiverse or world hopping FF before reading the story. I'm pretty interested how Julian's presence is gonna change the plot and if Subaru will be more tolerable and have less mental breakdowns cause he has someone by his side in his return by death.