Pretty much the only time I shoot jacketed bullets is when I get them for free, or out of something where the ammo is cheap, like the 7.62x39.
I cast all my own handgun, and some rifle bullets. But, too hard of an alloy can cause even more leading than too soft of an alloy, especially if it's not sized to the bore properly.
I cast bullets for the 9mm, .38/.357, .40 S&W, 10mm, .44mag, .45acp, .30 Carbine, and .30-30. Most of my reloads are close to max, and they are moving just as fast as jacketed bullets. Just slug your bore, and size the bullets .001-.002" oversize and use a plain base bullet, and you won't have leading problems.
If the alloy is too hard, it will not expand to the bore, you will get flame cutting when the gasses pass by the side of the bullet, it will melt the side of the cast bullet as it passes down the bore, and you will get leading. I use straight wheelweight alloy, even in the .30 Carbine or .30-30 Winchester at 1500fps, and have absolutely NO leading whatsoever. My 10mm's are going over 1100fps out of a 1006, with no leading, either. .44mags with 22gr of 2400 powder with a Lyman 429421, no leading.
But, if you are shooting very soft swaged bullets instead of cast, I can see why you have leading problems.