Your repair will be fine. Butt splicers make a Strong, insolated, very low resistance connection. They will not fail. Our power lines to our house use them.
If you use a good quality insolated butt splicer like Stake On, for the right size wire, strip about a quarter inch on both wires, slide them untill the insolation butts against the inner conductor, then crimp it, it will out last the bike by a lone time. and have no more resistance then a peace of wire, and is well insolated. As long as you have room for the little bump.
At todays labor rates it would not make sense to add a couple hours to the job.