The Suzi gauges are the same as the Evinrude gauges (supplied on ETEC and later DIs) and give a digital display on "essential" EMM information.
The EMM has the ability to produce detailed information on the engine whilst the gauge sticks with the essentials.
I think, and probably agree, that the manufacturers have gone as far as supplying the end user with adequate info to operate safely. It would indeed be very easy to present full mangement systems but the consequence would be less pleasure of boating and more sea borne computer nerds with the resulting paranoia. After all , our cars have EMM systems but no diagnostics at all.
We often supply our commercial customers with a PDA fitted with diagnostics. This only
to serve the e-mailing of data direct to engineers if ever a problem. This saves time waiting for an engineer to attend but is not intended for the end user to undertake unqualified investigation of the engine on a daily basis.
Alas there is the fine balance between need to know and want to know.