IMHO, I don't think moving ribbon over indicator is good interaction as it contradicts general mental model of moving marker over a range of values. e.g. setting temp. on thermostat, volume on audio mixing device etc.
However, if you want to stick to moving ribbon -
1) Do not show indicator as a control, just making number bigger would suffice rather than having a circle around it. Users move indicator because it looks like a control.
2) Or best way, separate it from ribbon by some distance
3) Or just show a pointer/needle in the middle (like you have shown) without highlighting number on pointer
On touch based devices, it makes sense to move ribbon if you can not show all range values in single view. e.g. setting date/time on mobile clock