We don't have any ability to customize UIs yet, although we're certainly open to feature requests.
We do have a "Record Page" for each individual record that shows a tabular view of related records from other tables, here's a screenshot from our website: https://mathesar.org/_app/immutable/assets/step-2.CKT9S1j0.a... - you can create new linked records directly there.
* do unit conversions by a multiplier - showing converted values in ui and converting on read and store
* hiding some (empty and irrelevant for specific situation) fields conditionally on values of other fields
would make this a much better fit.