The extra features are worth the price if you want those extra features. It'll likely cost you more to add those features to a bike that doesn't come with them if in the future you should desire them. But for certain they'll be a waste of money if you don't desire them or need them.
I always just advise those that are new to cycling not to make their first few bike purchases a drain on their wallet. Buy a bike that you can easily afford to replace if after riding a year or so that you realize it really isn't the bike for you.
The Endurace might let you sit a tad more relaxed and upright. Which I'd think beneficial for riding in city traffic that is stop and go. But depending on exactly which size frame you get the Synapse might also allow that. And for sure you can probably find a Synapse to try. The Endurace you probably have to order blindly and just depend on the return policy if it doesn't quite fit you. Or are there dealers in NYC that actually stock Canyon's?