I’m not so sure about that. In OH 4 there are several great additions added to sitemaps (support for material, f7, and iconify icons and a new input element that accepts free text). There are lots of users of sitemaps, even among the maintainers.
By Dashboard do you mean HABPanel?
Over all I think it depends on how much control you want over every little detail and how much work you are willing to put into it.
Sitemaps are super easy and quick to set up but you have limited customization ability. It’s just one Item per cell, two cells per row (one on small screens).
MainUI Pages sits somewhere in the middle. If you don’t want to do too much work to set it up, you get a lot just by putting your Items into the semantic model. But you also have a lot of freedom to combine and build unique widgets to exactly meet your needs, if you are willing to dive into the underlying F7 framework options. MainUI Pages are also responsive, unlike HABPanel which required you to build a separate panel for each screen size. There is also a growing collection of third party widgets you can install and use from the marketplace so you are not entirely on your own for creating the widgets.
Note that there is also HABot which has some relatively light weight NLP processing that lets you interact with OH using natural language queries and commands and build up adhoc views of your Items on demand.
It’s all JSON under the covers. YAML was the most straightforward compromise between raw JSON and something at least approaching human readable that can be used across the board for all OH entities, not just widgets. But if you have a better way, Issues are always welcome.
This confuses me because we can test the widgets live in the widget editor. When developing a widget under Developer Tools → Widgets the panel on the right shows the live view for what you are writing. There’s a ctrl-p lets you set the properties so you can test it out with different configurations.
In the “default x wdiget” metadata form for Items there too you see the live impact of your configurations at the top of the screen.
Where are you not seeing the live updates from your changes?
You really should go through the Getting Started Tutorial again(?), particularly Pages - Custom Widgets | openHAB in addition to in the main docs Creating Personal Widgets | openHAB. You absolutely can define input parameters for widgets.
Are you trying to create widgets on the Layout pages themselves? If so, yah, don’t do that. Create custom widgets using the tool sited above instead.
Also, I’ll mention the developer sidebar (alt-shift-d) which includes an expression tester which lets you build up and test widget expressions.
We don’t market ourselves and the nexus of activity is here on our forum (or if you speak German there’s the Facebook page and I think a Discord, I don’t so I don’t go there). It’s all volunteer effort here and we are not great about marketing and reach out. We are also pretty laid back and non-competitive. If HA works better for you, great! We’re not going to try to dissuade you or bad talk the other platforms. That puts us at a disadvantage I think but we seem to be OK with that (volunteers are requested if someone wants to take on the task of outreach, marketing, and outside community involvement).