My only concern (from experience) is if or if not the garage loft if heated or cooled...I suppose in Maine, the cooling is not too critical but I highly suspect winter extremes in the LOFT
I have ample attic storage here for my ever increasing fleet, but due to the temp extremes would not consider ever hanging my hard work in a 160-F or near zero-F environment
As it is, we had to suck up the cost of electricity for my Building barn/shop to cool ME to a comfortable 80 in the summer (105-F outside). And at least 60F in the winter ( 25-F~45-F typical)... supplies, paints, glues, balsa stock, kits to consider---but more importantly I got cheap fluorescent lights that do not fire and run without flicker in the sub 60F range...Yes there are better options and ballasts or even now LED fixtures ---but my 7 each 8' two tube fixtures are still providing good light as long as I do not try to light them at 40~50F indoor temp
MY dad did a very similar rafter set of plane hangers, but using 3 inch W x 4 foot L strips of Peg board nailed to the 2x4s