Scriptable e-mail client app with good formatting

I have a design-oriented client who has been struggling with some shortcomings in how Apple’s default Mail app handles font styling. When they copy-paste, styles inconsistency change, larger font, switching to a default font, etc. All the problems happen manually as well as with script generated message. We have exhausted all the avenues of different composing settings and begun exploring alternative client applications.

One “almost” contender was Airmail which allows nice scriptable control over styling, a generally adequate script dictionary… but, it too quickly showed weird style issues that were almost worse than Apple’s mail.

I realize not everyone may have such hyper-sensitive clients but I thought it was worth reaching out to ask if anyone knew of any good email apps that (at least) have excellent AppleScript support (regardless of your knowledge of their font handling).

Thanks for any suggestions.

It’s important that the app allow mail creation (text and/or html) but also manual editing… and it’s there that things break down. Even creating a message manually, and then copy/pasting text in Apple’s Mail causes the results to have mismatched fonts. Normally you don’t notice this with plain text emails or when using the default font… but it happens and is especially obvious when you have a custom font selected.

Hi: I normally use Outlook, which is pretty scriptable. However, I have a Filemaker solution that uses SMTPit Pro, a plugin which is also quite capable.