Is voter suppression a big issue in US politics?

A record mid term turnout still had less than 50% voting and this is scarily low in a democracy. I've read about all sorts of logistical problems: hour long lines and machines but I working etc. Also, it is harder to register to vote than in other countries, with struct ID laws and life bans for ex felons. Gerrymandered Congress districts and two Senators for every state regardless of population seem ridiculous to me.

How can such an inbalanced and weird system decide so much?

Is this by accident or design?