I’m playing on the hardest economic difficulty in career, but I’m still always flush with cash, giving me a huge cost advantage over my enemies. This removes a lot of the challenge for me, and encourages me to make huge laggy ships. I know I could artificially challenge myself by purposefully wasting a ton of money, but doing that is really unfun and demotivating for me.
I wish there were more economic difficulties, to force me to care about making ships cost-effective. Not sure what you would call the harder difficulties, but maybe architect and engineer?
