I'd keep the frame upgrade components and invest in wheels.
However, If you are really dead set on buying a new bike and it's a size 54 I might be interested in the caad9.
Unless your spindle is shot, all you need is new chain rings if your current chain rings are worn out. new -take-off 105 can be had for fairly inexpensive.
Honestly I prefer the older 10speed 105 over the new 11 speed 105. Buy a new cassette, a new chain, new chain rings, New shift Cable. New bar tape, and a super awesome set of wheels and good tires, GP4000 or the new GP 5000
I have a set of Shimano RS81 C35 wheels. that I am not willing to come down on price and sell what people can much cheaper wheelsets for. So I have been looking at caad9 and caad 10 frames to put them on as a N+ 1 bike.
A caad9 is not irrelevant. guys in this Thread/topic can really help you out far more than the guys posting/reading in General.
https://www.bikeforums.net/road-cycl...-caad-409.html