Just wondering if by your saying “Picked up a few Doug Tipple flutes” means that your tried them on for size briefly or that you bought, owned and worked a while at playing them?
Yes, there’s a bit of a stretch - it’s in the physics after all. But the two Tipples I’ve owned were not terribly difficult to play. I have smallish hands. A flat-finger grip is a decent solution.
The embouchure hole on some early Tipple flutes was not ideal (smallish and round). That could put some people off of a Tipple. But the latest cut (oval-ish) works well, IMO. The bore of the flute should not present any big issue. If you hit the edge well it should be pretty air efficient. It’s not like a low whistle.
So if you do own a Tipple I’d suggest you keep at it. Try to employ a flat fingered grip, more like a piper’s grip, to address the stretch. Otherwise,sure, look for another flute.
Yep, as suggested above, Copley (3 piece) or Somers (3 piece Pratten). Good flutes. Good value from both makers.
That’s another good choice, friendly finger spacing.
I’ve also owned several delrin Dixons, polymer M&E’s, delrin Seerys, etc.. I’ve played most of the others available too. The Copley and Somers flutes are my preferences for polymer flutes. I’d agree with Plunk111’s assessment of the two. 
Well, not exactly. AFAIK Copley does offer a particular hole layout for smaller hands. I’ve owned both the “small hands” Copley and the “regular” Copley 3 piece delrin flutes. There’s really only one hole that is different in the “small hands” layout. That brings the BH2 and BH3 holes a bit closer together … but not by a lot. That could be a deal maker/breaker for some players but I personally don’t see much of an ergonomic advantage to it. The smaller hole effects venting of certain fingerings as well. I’d suggest getting the “regular” layout. The Copley holes are not particularly large. You should be able to handle them easily. Again, look into a a flat-finger grip if stretch and/or coverage are an issue.
Copley also offers two embouchure cuts on the 3 piece flutes. A rounded rectangle is standard on the 3 piece flute. It is more like a modern Boehm embouchure cut. It has a broader blowing edge and therefor an easier to hit sweet spot. That’s what you get if you do not otherwise ask for the traditional cut. The second cut is a more rounded, oval-ish hole which is more a traditional embouchure cut for Irish playing. Tone can differ a bit between the two.
Feadoggie
You might want to update your website. 