Thoughts on choosing electricity plan?

Is it still the standard go to 'powertochoose.org' and select the cheapest plan?

Currently have gexa which gives credits if we use >1000kWh and it's 22c for 500kWh and 9.2c for 1000kWh. However we always end up using less than 1000 so wondering if I should switch to a plan that costs 13.9c for 500 kWh and 18.9c for 1000kWh?

Second question, should I try to get a 6 month plan from any company and shop again in December in hopes for rates being better? TIA