"Are elevated glucose and low insulin problematic?"
Nope. In fact your numbers are excellent and typical for a low carb eater. For a complete analysis, I defer to Peter at Hyperlipid:
A LC eater has a FBG of 5.5mmol/l, technically pre diabetic, but blood insulin is 3.5 IU/ml. This is VERY low. Glucose is in very short supply but blood glucose is maintained by physiological insulin resistance, ie the muscles are full of triglycerides assembled from free fatty acids (NEFA) from lipolysis. The LC eater has breakfast, with enough protein from his eggs or particularly casein from his yoghurt to raise insulin from 3.5 IU/ml to 5.0IU/ml. This inhibits lipolysis enough to reduce NEFA in the bloodstream, intramuscular triglycerides fall and muscle insulin sensitivity returns. There's minimal glucose coming from the gut and so plasma glucose drops to between 4.0 and 5.0mmol/l, probably nearer 4.0mmol/l. It fluctuates between 4.0 and 5.0 after and between each LC meal. In the early hours of the morning there is a growth hormone surge and NEFA from lipolysis peak early morning to give insulin resistant muscles and an elevated FBG.
MEAN glucose over 24h will be in 4 point somethingish, HbA1c will be between 4 and 5%. INSULIN will probably average out around 5-10 IU/ml, averaged out over 24h.
A high carb eater with FBG of 5.5mmol/l implies chronic hyperinsulinaemia, 24/7 and is looking for something to die from.
A LC, very high fat eater with a FBG of 5.5mmol/l implies they haven't had breakfast yet. They are not going to be hyperinsulinaemic at any stage. Unless they eat a bagel instead of their normal bacon and eggs that is. If they do this their blood glucose will hit 10mmol/l before insulin can shut down lipolysis and get the muscle accepting glucose.
It's NOT the FBG of 5.5mmol/l that matters. It's what that means about insulinaemia if you are eating a rice based diet. It's bad.