A quick note: your spreadsheet had better support arbitrary-precision currency math, if it doesn't already. That's table stakes for a spreadsheet.
To answer your real question, I'd suggest doubling down on the sqlite side and taking things in a relational direction. Spreadsheets are good at tracking 1:1 or 1:many relationships, but my spreadsheets inevitably grow in a many:many direction and I find myself wishing for queries and junction tables.
Should you be interested in doing so, my suggestion would be to offer an "offline" version. It could be feature-limited as follows:
1. Do not include the planned online collaboration features.
2. Support only Excel, Access, CSV/TSV, and Sqlite data sources.
Charge a fair one-time license fee for this, and you would create an attractive tier for individual power-users, without cannibalizing subscription sales of the "online version" for businesses and contractors who care about collaboration and interacting with large production databases.
I would pay you $400 for this tool without hesitation. I would also pay for upgrades. However, the $400/yr subscription model is a deal killer. This is fine if you're targeting business users only, but it puts the tool out of reach for all but the most determined individuals.
You might want to consider the pricing model used for many digital audio workstations -- a perpetual license for a few hundred dollars, with free patches until the next major version. Then the next major version also costs a few hundred dollars. Rinse and repeat.
This gives you a solid income stream, without ripping your software out of the hands of a customer the instant they're short on cash. It also means the program could work without an internet connection or other constant DRM/activation nonsense. This will likely matter for the technical audience you're targeting.
> Important for these COVID-19-related findings was the lack of informal communication that the project team suffered in the absence of face-to-face interactions. In the past, JPL's success typically relied on senior members of projects and technical line organizations "walking the floor", dropping in for conversations at office doorways, or chatting in the cafeteria. Without these informal communication mechanisms, contextual clues and situational awareness were lost. Team members working the floor found it difficult to report problems up the chain over Webex, especially when attendees kept their cameras off."
> ... The lockdown conditions contributed significantly to the question of why Psyche and JPL leadership did not know of the severity of the problems with GNC and V&V until it was too late to correct course.
> ... The IRB recommends that, given these exceptional circumstances, the team should minimize remote work conditions.
JPL has been suffering a brain drain over the last few years, and it sounds like the remaining cadre of managers are not so competent. Remote work is a convenient scapegoat, but it is far more likely that the problem is an ossified chain of command and a lackluster set of communication tools (Webex, shudder).
A quick note: your spreadsheet had better support arbitrary-precision currency math, if it doesn't already. That's table stakes for a spreadsheet.
To answer your real question, I'd suggest doubling down on the sqlite side and taking things in a relational direction. Spreadsheets are good at tracking 1:1 or 1:many relationships, but my spreadsheets inevitably grow in a many:many direction and I find myself wishing for queries and junction tables.