Over the years I've seen numerous illustrations of "highway in the sky" concept. A display system that provides integrated cues akin to visual flight would be the most natural way to fly in the IFR system.
I wouldn't want to hybridize IFR/VFR procedures and safety margins. "See and avoid" terrain information based on a database would make me extremely uncomfortable. Was there a direct sensor system providing data, radar, whatever, interfaced, would be closer to satisfactory. That system failure would put you in the same box as an overly casual IMC encounter. IMC in the strictest definition, that is- instrument weather conditions that don't meet VMC definitions but still may allow controlled flight to an exit or landing.
That's the key IIMC issue in my experience, being prepared for the weather encounter. Leave room for expected weather to deteroriate: avoid mountains; circumnavigate extensively unlighted areas at night; follow your alternate landing areas en route if you're not prepared to operate IFR.