To answer the basic question, it's better to give two shots a day and lower the dose enough so that you can do two shots. And also lower your "no shoot number" so you can shoot twice.
As others have said, you are currently skipping perfectly shootable shots. The "no shoot under 200" is for brand newbies, which you no longer are. Once people have the data and experience to do so, people following SLGS can shoot as low as 90. I'm not suggesting you do that now, but work your way down to it. Maybe start with shooting 150-175 and above, and shooting your full dose, not a part dose. But only do that when you'll be around to monitor so you can gather data as to what happens. Then when you've done that a couple times, reduce the "no shoot" number some more.
The lovely thing about Lantus (and Levemir) is that shooting lower numbers leads to much flatter cycles. Take a look at some of the subject lines for the other cats in this forum. Study other's spreadsheets, I found that quite helpful.
As for following SLGS, another requirement is to do a weekly curve. You need to get some more mid cycle data to see how low the dose is taking your cat. Ideally you'd also get a before bed test every night, as a large number of cats go lower at night, and we need to spot those lows to figure out how to change the dose.
