Fleet or infrastructure?

Wondering at which points I should focus on building up mines and research and when I should focus on a fleet?

Thus far I have 3 colonies all very young (5-6 days of playing thus far) and a fleet capable of running missions. I have been attacked twice, but both times was ready with a fleet/resource save and lost nothing.

I just unlocked the Poseidon last night and will likely make a pair of them today but my mines are still in the low teens (13:11:11) on my homeworld and lower on my two new mining colonies.

Should I be building mines more aggressively for the longer haul?

hello there. in my honest opinion i think the focus could be like this..

beggining of the game 50/50 on fleet/infrastructure. lets u have generaly everything at an acceptable level

once u hit the colony ship - 80% infrastucture 20% fleet... build and COLAnise everything u can if you are not being attacked or dont have threats around you.. because the more u build now.. the better fleet u can have in the future

once all nine planets are populated and at a good level - 75% fleet 25% infrastructure.. build a mighty armada and own everyone lol..

for me im at the mid/end stage.. not long till i start my fleet

Thank you for the advice