If you take Paris you don't make peace with France. Rather "Create Vichy France" event will fire, once you get "Flank Maginot Line".. and you now own all of continental France in Europe except for the new country of Vichy France. Vichy France is not your puppet, nor your friend. And the Free French (Charles de Gaulle) will always hate you and their traitorous brethren the Vichy for having made a separate peace deal with Germany.
As regards the STR question, all bombers flying into extremely hostile enemy territory are effectively limited in range by their ESC/FTR (because flying without them attached is suicide). In fact, to be safe, you are also limited by range of your FTR as that is the only thing that can really protect the bombers.
With 1940 FTR-2 achieved your fighters can reach out 400 km, and ESC/FTR-2 500 km. But Warsaw to Moscow is 809 km.
If you want to risk losing your STR, STR-1 have range of 800 km only, but you could have STR-2 1940 by Barbarossa to so strategically bomb Moscow then.
But it is suicide and with very little going for it. Trying to keep the capital infra low in a big IC country simply is impossible. You need to bomb the whole country first to destroy most its factories so it can't repair the destroyed infra in Moscow. The successes I have shown using STR is because I have very many, they are later models, and I choose smaller targets. Yes, I can bomb Spain, Romania, Bulgaria and Hungary so they only have 1 IC, but I definitely can't bomb Germany to same even if it had zero Luftwaffe. And Russia is impossible because you can't reach most of it.
Much better is using rockets. Certainly hitting Moscow daily will reduce the effectiveness of the Red Army by decreasing Moscow infra a noticeable amount... but don't expect to achieve zero infra to have any units starving. But you will achieve "Lack of Supply" during combat... the amount of that negative modifier depending on how low you can keep Moscow's infra. Be prepared that AI SU repair speed will be very fast.
Finally, even with all supply from capital cut off, units will still get some supply from local factories producing supplies and/or supply draw from allies and puppets for some hours of the day when units can't get supply any other way.
STRATEGIC BOMBERS are really meant to be used strategically... and not grossly. So, a pocket of SU you are trying to eliminate but is getting supply from the factories in that pocket might be quickly put totally out of supply by one or two days bombing of those few but critical factories - with the result that then the Out of Supply modifier quickly climbs to -50 during combat; and enemy units eliminate.
Another example is giving one Logistical Mission to a province to reduce the infra to zero (if it is 4 modern STR) and while that is temporary until repaired, it could be crucial to delaying reinforcements so you enter the province first. But aiming to keep Moscow infra so low that it would affect Barbarossa a lot is very difficult for STR because they will be neither modern, not be very many and, mostly, soon all be shot down.
Finally, it takes more than bombing just the target province because the surrounding province infra will pump up the zero infra in Moscow to effectively be much higher than zero. So you need to pound Moscow AND all surrounding provinces to zero infra. But it is impossible to maintain actual zero ESE in the target given repair speed even if you had 16 STR wings and no enemy air force to interfere. But certainly you would greatly reduce ESE to the Red Army everywhere. As said, successful STR to attempt this kind of thing first destroys the country's IC so province repairing is not possible.
Going to have to re-think my funky strategy for the next game!