One question I have is, how old are you? It makes a difference if you are trying to avoid complications for 60 years, or only 10 or 20 years.
BG control is a tradeoff. High numbers, over time, will cause complications or in bad cases cause DKA (Diabetic Ketoacidocis), but LADAs still producing insulin don’t have to worry about DKAs yet. Low numbers can kill you quickly, so avoiding hypos is paramount. Studies have been done on both T1s and T2s (ACCORD) that showed that intensive therapy actually increased mortality, but they didn’t follow up to determine exactly why. I presume it was because hypo events increased because their targets were lower. If you have low BG target ranges, make sure you have methodology that minimizes hypo events.
In my case, I was misdiagnosed T2 at age 57, diagnosed T1/LADA at 59, and an currently 61. I take 6U of Lantus per day, and only need to take Humalog for meals greater than 30g carbs, with 1U/30g over that initial 30g threshold. My target BG range is 100 to 130, and I consider anything below 70 as “low”, with the range 70 to 80 as guard band. I typically have ~150g of carbs per day, with one or two meals needing a bolus. My last A1C was 5.7. I figure I am in the extended honeymoon that LADAs get where control is still easy, and I am trying to enjoy things now before they get harder. It took some work to get most of my meals to have about 30g carbs, but now it’s easy to eat that way, with some excursions. Spreading your carbs throughout the day will limit spikes.
You can keep your numbers in line quite well with just diet and exercise, but it is noticeably harder and less fun than if you have the medicines to support it. Getting an appropriate basal insulin would do the most good in keeping your A1C in line, while allowing a more normal diet.
If you want to trim you “spikes” for higher carb meals, you would need to bolus with a fast acting insulin. In some cases, though, the bolus plus your pancreas will handle the carbs before the bolus is “spent”, so you need to test for the possibility and “feed” the insulin to prevent a hypo. This is inherent for early LADAs and not necessarily an indication that the bolus was too large. In my case, I test two hours after my meal and if necessary have a greek yogurt (18g carb) or glucose tablets to cover the remaining insulin. Other LADAs on this site have had good result with Afrezza, which has a reputation of getting out of your system quickly.
As for pizza, I am happy that with 1U of Humalog, I have a reasonable BG curve after eating two slices of pizza (60g carbs), which is one of my favorite excursions. Good luck, and test a lot to learn what works for you.