Congratulation to your first Patek!!! PP 5270 is a great reference, but I also like not that the sub-register are not in the „crown line“. A little bit unbalanced. Why Patek done this? The Lange Datograph maybe could be the answer ;-)
Yes, you should sell the Lange 1. If you miss it you can buy it back. Lange 1 is for me yellow gold with champanger dial. The regular style PP 5235 have a nice dial in the wrong case. The form of the case is very similar to the old reference 3450 (perpetual calendar) - this case with a perpetual cal