Service looping is a fiddly job at the best of times. For many years I have used tools designed for PCB re-work, you can modify them as you need, from a very fine point to grinding back to a snubbed nose. However, I was recently visiting the fantastic team at Project DC
Project DC and they are using this compact punch, it is the Beta 32 3mmx100mm. Very compact and a good-sized tip for most service loops and it is available for under £10 online.