The options for building/deploying apps with NativeScript are generally the same as Apache Cordova/PhoneGap.
If you're using AppBuilder, you don't need a Mac. We'll do all the building in the cloud for you (just like with hybrid apps). From there, you can either:
A) Deploy to your local device (and take advantage of LiveSync updates as you make changes), OR
B) Use the NativeScript companion app to scan the build QR code instantly load the app on your device
The cool thing about NativeScript (compared to Cordova) is that you generally don't have to worry about plugins in the companion app because NativeScript takes care of all interaction with the native APIs. That means the companion app should be useable for testing more of your app code (before you do a full install of your own app package).
If you do want to use the iOS Simulator, then yes, today you'll need a Mac. We're working on that, but as you noted, there are some "hurdles." If you have a Mac and AppBuilder, you should be able to launch and run the iOS simulator directly from your non-Mac machine:
Hope this helps.