Tartan... what a beautiful quilt! And what a blessing it will be to the recipient!
This is just my opinion, but from what i see in your photo you couldnt go wrong either way. Since you asked - i would vote for no border just because i dont necessarily like to do borders myself and i can see your quilt finishing just as beautiful as it already is without a border!
I have wondered the same thing often - border or no border??? Borders just arent my favorite thing to do. Certain patterns call for them and i have no problem technically executing them, but i just dont like them much! I dont enjoy adding them or quilting them but i do concede to throwing them on when necessary. Not sure if any of that makes sense!
Sometimes you dont have much choice because the quilt just needs to be bigger. Been there done that. Because i dont like borders much, i usually opt for just making extra blocks if needed for the sake of size. Whats a girl to do???
I am probably in the minority in this discussion, but i would say that a whopping 95% of the quilts i finish have no actual border. If i think the quilt still needs “something” to make it “pop” i might add a pieced binding and i am usually very pleased to call it done! Sometimes its important to add a binding in a single color to give the proper finish and “stop all the action” going on in a quilt.
Most of the time i avoid running afoul of the Quilt Police. If not, let ‘em come!