The Lange collection doesn't seem so large compared to many other brands but in fact when you learn to go deeper in the collection you discover that they are all really different and complementary.
My first advice, as I went through this myself (and may be still on the way^^), is to go and see all the models in a Lange retailer. You may go finally for a watch that you didn't think of, at the beginning.
The fact that some are "automatic" is not at all a problem : everything depends on what you will do with it in you life. For example, I was strongly thinking about acquiring à Dato (manual), what we can see through the back glass is stunning.
But once I felt on a Langematik Perpetual (I know it's not the budget but it is just an example), I realized It is an amazing watch, but I had to forget the dato's back show. Finaly I know I will wear this watch as an everyday watch and I'm not necessarily fond of the manual winding. Thus, the automatic winding would completly fit my needs. The size inperfect for my little wrist. The complication is there too...
So I would trully recommend you to go and see them (not only on the net or in a catalog), then ask yourself how your are going to use it. Make your decision mature and .... go for it !
Conerning the watch, I would say the SaxAC is beautiful and dressy, with a great finish, and a poetic complication, not the same price than a 3 hands watch but it is really worth it.
Best,
Mark