Awesome! I do have some thoughts, and I hope some of this is helpful!
I will say, in the interest of full disclosure: I kinda think right-to-left comics can hurt the flow of the comic when the comic is made to be in English. I know it's a tradition for manga and comfortable for people who've read lots of manga, and I heck, I got used to it when I was reading manga, too, but here's the thing -- by having English (which flows left to right) and art that flows right-to-left, you make it a little harder for you, the artist, to control the natural flow of the reader's eye, because you're pulling it in two different directions. And most of the manga we read is drawn by people who naturally think in a right-to-left flow, because that's how their language goes -- if you don't naturally think that way, it might trip up some of your flow and placement.
BUT!! That choice is yours; I have said my piece on that SO!!! I'll focus on the flow of this as being right-to-left. ;u;
Your art is quite lovely! I think your expressions can be a little stiff in places, and the figures have kind of a rotoscoped look to them sometimes with that deadline lineart, but I dunno, that's kinda working for me, honestly!! Your figures have a really neat style to them and your perspective feels very natural.
Most of my in-depth thoughts are actually more about structuring the page and leading the eye! First, here's a pretty minor thing to keep in mind with the size of your pages:
this isn't an issue of left vs right, but of scrolling down a long page -- something I've run into as well on Tapastic. This screenshot is around how much of the page I can get on my screen at one time. As I'm scrolling down, even though I know to read the right panel first, I won't see the whole panel right away -- I'll see the tip of the monster's head with an empty panel beside it, which will draw my eye towards the monster, and then I'll see the face in the right-hand panel. I can sort of take these panels in simultaneously, or I'll do a weird thing where I try to ignore the monster to scroll down and make sure there's nothing important in the girl's panel before I go back up and look at the monster, but either way, I'm not going to get that nice beat of
-> girl looks up
-> see the gross monster she's looking at
because even though the panels are in that order horizontally, I'll see them in the opposite order vertically.
Whenever you do long panels this is something to think about; readers will have to scroll down before they can see the entire panel, and it's tough to pull off something where people need to scroll down to the end of the panel before moving left.
Once word balloons show up, the shape is a bit awkward -- I'd go for something more like:
1) your word balloons have a HUGE amount of empty space on the top and bottom, and then in the middle all the words feel kind of cramped -- in some cases they even scrape up against the sides! I know lettering is a secondary thing, and believe me, I don't put as much effort into lettering as I could -- but it really does make a difference!
I get the feeling you only have one, like, proportion of ellipse and you're flipping it so it doesn't cover up important art -- I would super encourage you to try working with the pen tool or something similar that can give you a more customisable shape, so you don't have to take up so much extra room with a poor-fitting balloon!
2) I moved Auntie's balloon. There's all this open space on the floor and ceiling but her balloon is crammed right in beside her, where it's also running into Vairyne's head -- it makes the whole panel look a lot more crowded.
3)If we're reading right-to-left, we're going to see "so it's not that late" before we get to "I just started breakfast" -- but it seems like "it's not that late" should be a response to that balloon? So it really needs to be in a place where we'll run into it after that balloon.
This next piece was a bad flow problem for me; I ran into this and was GENUINELY unsure where to start. (I flipped it and flipped all the text while I had it in photoshop, just to make sure I wasn't being unfair to the right-to-left orientation, but even in my natural orientation, it's still got a pretty rocky flow).
First off, you have another thing where it seems like you need to go down before going left, which is a little tough to pull off in a scroll-down vertical comic, but it's not the worst -- Bromin's balloons do lead down into the potatoes balloon. But after that... it feels like we went the wrong way, because that balloon leads right into "I wanna know how some high-society brat...," which is obviously not right. We're supposed to hit the potato balloon, then skip over the high society brat balloon, to get to the "city girl's awake" balloon, which none of the balloons on the right lead into. Then after we finish that panel, we need to move back to the right again, which is fine, except we run into both "we were fine..." and "enough!" on the way there, before we get to the balloon we're supposed to get to.
What all of this does is pull us out of the story because we have to consciously determine which balloon is next. Even if that process takes only 1 second, you never want the reader to have to stop and think about this. As soon as the reader has the split second thought of "wait, is this -- oh okay, this is the next balloon over here" you've pulled them out of the story.
Here's a less complicated example of this issue-- on the page where some guys are talking about how the girl must've brought night terrors, "people are sleepwalking right out of their homes" doesn't lead naturally to "better them than us":
Since that first balloon leads down into the "brought the terrors with her" balloon, we end up having to read the panel in the wrong direction to get to "better them than us."
You need your balloons to lead the readers eye so that they naturally move in the correct direction -- you never want to pull them back the wrong way. Here's an example of what I mean:
This might not be perfect, but it fixes the flow problem -- if your eye is moving right-to-left, every balloon leads into the next one, and you never hit a balloon in the wrong order. And as an added bonus, the cat is leading us down into the next tier of panels! Perfect!
It legitimately blew my mind when I first learned that comic artists think about this all the time. Every balloon and every piece of the artwork needs to contribute to leading the eye in the correct direction -- whether you're going to do right-to-left or left-to-right, everything needs to point your eyes naturally along that path.
When I'm first doing the rough sketch of my pages, I'll actually draw a big arrow on the sketch like the ones I keep drawing on top of your pages here, to make sure everything's flowing the right way and I'm not making my reader's eyes run into the wrong balloon at the wrong time!
I know these comments are more structural and general, but I hope this is helpful! Let me know if anything I said is confusing, and I'll be happy to clarify as best I can!!