What I would find really helpful is if the resouce symbols become highlighted on the main map once you have the required tech and have colonized the appropriate planet. basically so you can differentiate at a glance the resources you have access to. Or even different coloured highlights. one for when researched and one for when colonised. Also it would be helpful if the number of resources you have were displayed in the diplomacy screen. I feel these changes would make the management of resouces much easier and user friendly.

Agreed. I like the purple/white for strat/lux resources on the main map, but I learned the designs that they use (atom for anti-matter, flower for proto-orchid, etc) quickly. Can the designs be white when discovered, but purple when utilized, for example?