You should be able to achieve what you want with the Custom Wizard Plugin 🧙 on the free tier. And your community will almost certainly qualify for the free community subscription if you do in fact need more advanced functionality.
I’d approach this by:
- Limiting the exposed UCFs to what you want to collect from casual members
- Use one question to identify those who should be full architect members
- This UCF can then gate a joining Wizard, which can be used to put them in a specified group and ask all of the other UCFs / data that you need.