Swallowtails in the garden, but which kind?

It's not easy to identify butterflies when they're fluttering around flowers.  Even when they've stopped to sip nectar and have settled down long enough for me to take a picture, I often find myself unsure of what specific species I'm photographing.  

Below are a few of different kinds of swallowtail butterflies (and one look-alike mimic) that have visited our gardens over the years. 

A palamedes swallowtail (Pterourus palamedes) on bottlebrush bloom

The pattern on the back of a palamedes swallowtail (above) reminds me of a heart.

Red-spotted purple (Basilarchia astyanax) is not a swallowtail at all even though it looks like one. 

Instead of being in the Papilionidae family like swallowtails, the Red-spotted purple (above) is actually a member of the Nymphalidae family. It is said to mimic the appearance of the pipevine swallowtail in order to fool potential predators.

Spicebush swallowtail (Papilio troitus)

The spicebush swallowtail (above) is one of the swallowtails I find more difficult to ID because I think it looks very similar to the female Eastern black swallowtail (below).

Female Eastern black swallowtail (Papilio polyxenes)

Not all swallowtails are as easy to tell apart as the male (below) and female (above) black swallowtails.  To me, the two look like entirely different species instead of just different sexes.

Male Eastern black swallowtail (Papilio polyxenes)

Since the wings of tiger swallowtails (below) are predominantly yellow with black stripes instead of being mainly black, they are much simpler to recognize than most other swallowtails.  

Male Tiger swallowtail (Pterourus glaucus) on bush sunflower blooms

In Tiger swallowtails, to tell the sexes apart, look for the colors.  The female (below) has noticeably blue highlights on her lower wings while the male's wings (above) lack that coloration.

Female Tiger Swallowtail (Papilio glaucus) on bamboo

And last but not certainly not least is the Giant swallowtail (below), which has a distinctive wing pattern that makes IDing it just a little bit simpler.

Giant Swallowtail (Papilio cresphontes)

Hopefully, I've labeled the above butterflies correctly but if you think I'm wrong, please let me know. I want to improve my ID skills and am always open to help from others.