I’m thinking about getting a Waterfront wool jacket from Aero leathers. The shell is an 18oz mackinaw-like wool. There are two lining options (alpaca and cotton twill). I live in Southern Indiana not far from Louisville. I’m afraid the alpaca liner would be too warm for fall when it’ll get down to the 40s or 30s at night, but up into the 60s during day. Is alpaca too warm?