I also used to split my Lantus dose, taking my evening dose, which was 1 or 2U lower, with my dinnertime Humalog around 8pm. I had a hunch, à la @cardamom, that a little alcohol always helped, but handling the DP was still hit-and-miss. (And there was no way in Hades I was going to set my alarm for 2 in the morning.)
As well, I plunge mid/late afternoon every day (just naturally – it happens regardless what I do with food/insulin/fasting for the previous 8 to 12 hours, and believe me, I tried every configuration), and Lantus was useless at coping with that. If there hadn’t been a tubeless pump option, I might have experimented with another long-acting, but with a pump I can adjust with a small increase for DP and, in the afternoon, drop from 0.55 to 0.15 for several hours before going to 0.95 for the evening. Not sure any long-acting insulin could do that for me.