If you have read my earlier comment a 4.4 output for the convenience since a lot of people like myself have 4.4 headphones and iems. Never once have I said balanced being superior in SQ.
I have a mix of DAPs, dongles, 3.5 and 4.4 headphones and iems which I alternate, grab and go to commute. I don't always want to remember carrying an adaptor.
Kudos to you for having a "super low profile" fiio adaptor mine is a cable type.
How many dongles or DAPs in todays market comes only with 3.5?
It's not a technological breakthrough to ask for a 4.4 for user convenience? Cayin already done it and it's cheaper.
At $300 for a dongle, I'd say is premium and Hiby should have 4.4. Again, YMMV we all have different needs.
Really, let it go lol. I'm just saying it's possible to get use and adapter if you don't have regular 3.5 cables. It doesn't have 4.4, and no amount of whining is going to change that. Maybe it was because of space constraints, maybe they just wanted to concentrate on 3.5 out. Idk, but there's a simple solution- don't buy it! As far as an adapter I have multiple iems and cables so I just keep it connected if I'm using a 3.5 source with that iem for a while.
And there are times when the balanced out is better than the 3.5 jack on a dap, in case that's been my experience. That's why I have many balanced cables. But there are times obviously when something has a really good old fashioned 3.5 out. Then I've got my adapters if I don't want to use a normal cable. Honestly it's not any more trouble than disconnecting and connecting your USB to its source. It literally takes a second or two.
Anyways buy a cayin then, this is the second time you mentioned this. Or if you have one and are happy with it- why are you here? I mean I just don't get the point of it? You think it's overpriced? OK, you don't want to carry or remember an adapter lol, OK. Sounds like this isn't the dongle for you. Do I wish it was priced lower? Sure I do, but it's not, so I either suck it up and buy it or I don't. See easy

And yes different people have different wants and needs, that's why there's different products.
There are tons of products out there that don't 'fit my needs' but I don't go on their info or web page and complain about what they lack or even about the price- why?
Because it's pointless and a waste of my time, and I know the world doesn't revolve around me. And they're are countless other items that fit my needs. Just like there's countless dongles with 4.4 outs that are less than 300 dollars.
I will say the ibasso dc03 pro is one of the best dongles I've heard and it's 3.5 only. 4.4 would be nice, but it's tiny and sounds so good. Anyways enough of this silliness, seek help.