For peaceful mode players, glitch ingots (and, by extension, glitch armour) is completely uncraftable. Since peaceful mode players are probably as interested in early creative flight as non-peaceful players, it would be nice if there were some means of obtaining glitch ingots without trials.

People playing with the added challenge of monsters and bothering with DML trials are rewarded with a really strong creative flight armor set + sword, I don't see anything wrong with that. The armor and sword don't matter for peaceful players, so only the creative flight ability interests them here. It doesn't replace jetpacks or the angel ring, or the hook and glider, it is just another movement ability you can get should you invest your time and effort in. I for one still use the ender hook and glider to travel more conveniently for example, flight is just a nice bonus.
Is it fair to peaceful players? You have other options for movements, the armor set is just one of them. If it is that easy to get maybe you should turn on easy mode and do those trials then, you can make yourself a bunker just outside the no-build arena zone and you'll do just fine. Just click at the monsters, it's not that hard. You just need two self-aware trials for the armor set, done in 5 minutes top.

Also to note, if you wear the DML armor, you can't use the ender io armor which is better in every way but flight (night vision, speed boost, step assist, etc)

Glitch armor is something of an anomaly in Omnifactory. The pack is not contingent on exploration or combat, which lends itself strongly to peaceful mode gameplay. The way I see it, it's a bit of a reward for going out of your way to do combat grinding in a pack that doesn't even tell you that it's a thing you can or should do.

Peaceful players gain creative flight access via the Angel Ring. They also have access to the full spectrum of hooks, EIO teleport items, and jetpacks. While not creative flight, these are more than sufficient for the minimal exploration the pack calls for; myself, I rarely bother even making anything besides a hook until I can craft the Angel Ring.

The armor isn't without its downsides. You need to wear the full set of it for flight, whereas other movement items are largely baubles. This prevents you from using alternatives like EIO armors which have very useful features via its upgrade system.

Also, if we add a peaceful recipe for glitch hearts, nobody will bother doing the combat trials. If the recipe is available at the same level of progression as Glitch Armor is available, basically all the other pre-Angel Ring movement items will become obsolete; everyone will just craft Glitch Armor.

I think Glitch Armor is too strong for how easy it is to get, and the combat aspect of it goes against the philosophy of the pack. It's my belief that it was an oversight that it exists rather than intentional; frankly, I would be more inclined to remove trials than promote the armor set. However, I'm also not anti-fun and I know that players like the option.

I mean, many players aren't using flight for exploration, or indeed, for any movement on a large scale. Flight is just a convenient tool for moving around large automation setups, as the alternative would be to build big towers of junk blocks to access the out-of-reach sections of a build, which is rather annoying. Moreover, the jetpacks available at earlier tiers are considered by and large unusable by many players because of their abysmal stats (possibly one solution here would be to buff them?).

I agree that adding a simple recipe will mean that nobody will ever do a DML trial again. I don't necessarily consider this a bad thing, since combat is not supposed to be a significant part of the pack's gameplay.

As for the "strength" of glitch armour, I am of the opinion that players should get early access to strong movement options. The core gameplay of the pack revolves around building scalable infrastructure and automation; limiting the mobility of the player only serves to add an artificial layer of tedium to this task rather than making it more difficult in any substantial way. Providing strong flight options allows players to focus their attention on the automation puzzle rather than wasting time jumping around and building scaffold structures.

Creative flight as a building tool is really not that much of an issue in practice. Peaceful players have access to the Red Hook which is limited-range creative flight anchored to a block. It costs basically redstone and a diamond hook. Between that, Building Gadgets, LittleTiles, and EffortlessBuilding, you'd have to really be going out of your way to contrive a situation where it's too difficult to build your base.

I've talked with the dev team about it and we're pretty unanimous on the aforementioned position.