Some thoughts: I used to type on an ISO-keyboard as well and did not like the need to type on an ANSI-keyboard, because of the Enter key and one key position changing. Then I moved to a country where ANSI keyboards are standard. After a bit of adjustment I much preferred to use the long Enter key of ANSI.
When you mostly type on your laptop keyboard and want to have the same functions like with your external keyboard just use Kanata. It is really great. It works so good that I even did not bother to program my external keyboard (now a columnar staggered one) and just have it on qwerty, but make all magic stuff in software. Will still program the keyboard (so it works in the Bios, login screen), but was busy … Kanata can also run from a USB-stick or Internet download as a portable program, in case you have a longer typing session on computer from someone else.
Regarding bugs with UHK. From my experience the UHK team was by far the best to answer my questions, implement ideas and fixed bugs quickly when pointed to them. So I am confident the UHK80 will work without bugs relatively soon. So either wait with your order or live with some niggles you now know are still existing.
Dygma seem also to be active, but my experience with Kaleidoscope (they use as a basis) has not been great. Possibly they will iron out the problems over time. Others like ZSA are not willing to really help to solve customer needs – that was my experience at least.
Finally. The Enter key is in a bad position when you think about it. I do not use it at all any longer now. A bit more than a year ago I changed my layout to a custom one (which you do not have to) but also came up with a layer system which is compatible between a standard and most keyboard types. I will upload a video and publish the UHK config and a Kanata file (for laptop use for example) to test it, hopefully in the coming weeks. But you can read about the concept in my post here.