SQL Backup routine regarding DB Logs
I could easily tune my sqlcmd scripts to do a &quot;backup in 'full' -&gt; switch to 'simple' -&gt; backup in 'simple' -&gt; revert to 'full'&quot; and keep the file at bay, but I fear I could be running some risk I am not foreseeing right now.

Don't do this. It is a horrible idea because it gives anyone else looking at the system the wrong impression and is only a workaround to lie to the primary developer. That is not a good reason to make a technical decision around database recovery. There are unknown risks since we don't know anything about your company, application, etc. so only you can speak to those.
The correct path is to get a consensus among stakeholders, including any stubborn developers, and agree on a RTO/RPO that meets the business needs. Then adjust the recovery model accordingly.
Assuming you don't want to do that based on your post:
If you are 100% sure you don't care about recovery more granular than daily backups, keep it in full recovery mode and have a transaction log backup job that points to NUL so that growth is not an issue. It won't save the files anywhere, but will still allow you keep keep log growth under control.
Also see:

Switching to Simple Recovery - shrinking transaction logs
expressdb.io: SQL Server Express Backups - Some more background on RTO/RPO and some sample jobs using Ola Hallengren's backup solution with some specific guidance for SQL Server Express.

Full disclosure: expressdb.io is my site.