6.1, 140lb, long hands and wear a 33 shirt size. Also long legs and 34 inseam

https://www.cannondale.com/en-us/blo...bike-do-i-need

guys - in market for a used bike but went into a Trek shop anyways to try sizing. The Madone 60cms felt nice and not too aggressive and fast enough for me. I can't find a Madone on FB but found a Synapse with similar geometry here -
I thought I'll need the Synapse 60cm but measuring per their guide, looks like 58cm may be a good fit. Problem is Cannondale doesn't public the old aluminum bike's geometry so I used the later carbon bike and 81.28cm standover correlates to 58cm. 34 inseam - 2 inches = 32 inches or 81.28cm. Another data point - my current Trek Alpha 1.5 is 58cm but feels a little small for me

Any thoughts if I'm thinking through this correctly?

Thanks!