.30-30 for sure.

Flatter trajectory with much lower recoil. If you load a .45-70 to same same velocities it freakin' kicks and you’d still not get the same trajectory.

Tons of bullets available, both flat/round nose made for .30-30 or any .30 caliber spitzer within reason.

Cheaper to shoot both for components or if not handloading it’s always among the cheapest factory ammo and available darn near everywhere.

Before animals got so tough the .30-30 was considered entirely adequate for darn near everything in the Western Hemisphere except maybe griz and some of them still got kilt with it. And that was with bullet designs we'd consider marginally effective.

Finally, a .30-30 single shot is just cool.

Gunnery, gunnery, gunnery.
Hit the target, all else is twaddle!