The new grip is good, I with the front side were a bit more rounded off, I might remedy that with some sandpaper. All in all, much better than factory.
Monarch is garbage, and if some care isn't taken with hps, lack of jacket thickness uniformity will fuck with bullet stabilization. I'll bet your rifle is fine, shit ammo.
That's exactly how it got the moniker, but it was created the 45 Colt...the fact that there was a short colt is why people started calling it the long colt.
If Dodge came out with the Challenger II and people started calling the original the Challenger I, that isn't the correct designation...
Have you looked at any old lever actions? Maybe an 1886? The new ones are fine, but if you want something special that might be the way to go. You just can't replicate the look, feel, history, and craftsmanship of the older Winnies.