There is an inherent offset in all SS drive trains. What you are experiencing is totally normal. All SS do this to a certain extent.
Consider this. The drive train is all made up of concentric circles. Cogs, bearings for hubs/bb's, crank arm bolt holes etc. If all of these parts are all made to a 99% perfect position, you'll have the compounded 1% error of each of those parts to the end result. Geared drive chains have the same issue, only the rear der take up all of the slack.
Really, what you have is nothing to worry about. Tension the chain properly at the tightest spot and you'll be good. So long as the tight and loose issue is not enough to have your chain fall off or skip, you'll be fine. Ride and enjoy.
Consider this. The drive train is all made up of concentric circles. Cogs, bearings for hubs/bb's, crank arm bolt holes etc. If all of these parts are all made to a 99% perfect position, you'll have the compounded 1% error of each of those parts to the end result. Geared drive chains have the same issue, only the rear der take up all of the slack.
Really, what you have is nothing to worry about. Tension the chain properly at the tightest spot and you'll be good. So long as the tight and loose issue is not enough to have your chain fall off or skip, you'll be fine. Ride and enjoy.