Perhaps after all of the current research tabs are completed, add a new research section indicated by a [Continue Research] tab? Or just after a certain amount of research has been done, as to allow new research options in the future. Each of these would cost a ton of research points for something that may not seem superb but at least its something to do with the extra research.
Example:
Tier 1- Planetary defense optimization:
Limit 1 per planet-
Size 1 Attack +9% Defense +9%
Size 2 Attack +16% Defense +16%
Size 3 Attack +22% Defense +22%
Size 4 Attack +27% Defense +27%

Tier 2- Specialized containment:
Limit 1 per planet
Size 8 Storage of your choice +1 hours' worth of production
Size 10 Storage of your choice +2 hours' worth of production
Size 12 Storage of your choice +3 hours' worth of production
Size 14 Storage of your choice +4 hours' worth of production

Tier 3- Ship AI Upgrade:
Level 0/3 (Like old resource structures)
[Basic AI 1/3] Shield module -1 second to recharge
[Basic AI 2/3] Scanning module +3% to total scanning
[Basic AI 3/3] Stealth module +15% to total cloak

Tier 4- Target Analysis:
Level 0/3
[Basic Targeting Systems 1/3] Attack Vs NPC +3%
[Basic Targeting Systems 2/3] Planetary invasion +3%
[Basic Targeting Systems 3/3] Attack Vs bases +3%
^All special modules under the weapons tab in a sub tab?

Tier 5 Exotic Endeavors:
Level 0/5 (Limit 1 per planet) (Costs ALOT of research points, even by high rank standard)
Size 2 All resources +1
Size 4 All resources +2
Size 6 All resources +3
Size 8 All resources +5
Size 10 All resources +7
I mean work it out somehow but the main point is that in addition to a lot of research, each structure will cost a LARGE amount of exotic matter. They could even work like the normal structure tabs.
[0/3]
[1/3] Size 4: Research +2 Artifact -1 Mining -1
[2/3] Same Minging +2 Same Research-1
ETC then progressively better and large size with better ratio, but still only ONE per planet.

+1
Interesting Ideas, hope something like this is added.