Is there a downside to having eyes done first and facelift at a later date?

Your plan for staging your procedures is perfectly fine.  Have already had blepharoplasty, chin work and fat grafting should not pose any issues. 

It is optimal to do the upper and lower eyelids and facelift simultaneously, as
there is one recovery of about 10-14 days. One can also do them out of sequence. One can do
the eyelids first and the facelift at a later date. The recovery
is similar, it is two operative procedures with two recovery times. This should
be done in the hands of a Board Certified
Surgeon with expertise in Facial Rejuvenation.

The only downside is two surgeries, two recoveries and if done in a surgery center 2 operating room and anesthesia costs. Otherwise as an elective procedure, it is fine to separate these two procedures

Optimally, all the needed procedures for facial rejuvenation should be done
at the same time, such as facelift and blepharoplasty. On the other hand some
patients elect to undergo just eyelid surgery and at a later time successfully
undergo a facelift, although on occasion some fine tuning of lower eyelid might
be required.

In general, I tell patients that the best money you can spend is on the eyes. Nothing makes you look better than periorbital, or eyelid, rejuvenation to get rid of that tired, puffy, wrinkled look encompassing the eyes. While excess facial and neck skin, and facial volume loss are a nuisance, they are second only to the eyes.So go ahead and treat your eyes first or do them at the same time, but not the other way around. "Here's looking at you kid,".....good luck.