Hi there
It sounds like he is now getting two naps of 1hr 15min and 1hr 30 min, is that right?
This isn't so bad at all, 1hr 30 is generally classed as a good restorative nap.
If his mood isn't good then maybe he would like a longer nap to get him fully refreshed, but I would also suggest looking at other possibilities too. Teething pain can certainly make a LO cranky during their awake time.
Regards the A times. You might get a longer nap if you extend the A a little. Like you say it is about breaking the cycle because a nap that is UT (under tired) will not be long enough to fully refresh him so later in the day he ends up OT due to the shorter than needed nap. I suggest increasing the first A time by 15 mins and hold it there for 3 days to allow his body clock to adjust. Keep the activity quite low key for that additional time.
This 'might' increase the first nap length (it might not, he might need another 15 mins added once he has adjusted to the first increase). You could keep the second A time as you have it at the moment until the first nap lengthens to avoid any additional OT or you could grit your teeth and see how he does on increasing this one too (could get that second nap back up to 2hrs). It's not an exact science and the times are only guidance, you need to see how your LO responds and work from there.
hope this helps
