Like almostawake wrote, if you are
really good, you should be aiming for NLB and maybe due to your dual nationality some team would pick you up. But NLA is a pipe dream at this point, you have to be roughly AHL level to play there and very few, if any, CIS grads are that good. NLB is not a terrible league though, some legios there can be crazy good too. Jussi Jokinen has signed a "holiday" deal to play for Kloten last year, for example. Maybe there are teams at the bottom of the league that would take you for a minor role if you impress.
I would suggest you stick in Switzerland because in other European leagues you will have little job security and legios are expected to put the points on the board, first and foremost. If you venture to a non-Swiss league pick the one you can actually score in. Which would lead you to the very bottom of the European hockey ladder where most CIS grads start - BeNeLeague, AlpsHL, Erste Liga. Maybe EIHL. But the pay first year will be enough to survive, not much else. Below 1k euros per month in a cheap country like Romania.
Eliteprospects has this helpful "where are they now" function where you can see the list of CIS grads and where did they end up, this way you will be able to ballpark your career path.
Elite Prospects - USports - Where are they now? . As you can see, there are hardly any players who managed to reach the top tier of European hockey.
To answer your questions quickly:
1) as hard as any pro hockey league not named the NHL. KHL, SHL, NLA have players paid well above the AHL level which means most AHL guys can consider themselves lucky if they managed to get a job in such league. After all, they are in competition with a lot of guys with NHL experience. If they aren't in such luck they will go to DEL, Liiga or EBEL. So those (and Czech league but it has very little NA imports) are the leagues where you have to be roughly at AHL level to play in.
2) It varies a lot. It depends on the league, the role, the country. You might get less money in Slovakia, for example, but the living cost will also be way lower than in Austria or Switzerland. So the bottom level wage will be enough to live comfortably in that given country. The ceiling depends on the league. For that middle ground, you can once again take a look at the AHL/ECHL wages. ECHL guys gladly move to countries like Slovakia, Norway or Denmark meaning they are being paid more there than they would be in NA. Star players in the ECHL are paid roughly 1k dollars per week and the average salary is ~600 so again, it's a little more than that in mid-level European leagues.
3) It's all about the money. Players are betting on themselves, they look to be paid more and more year after year until they peek so signing long term deal doesn't make sense for them. Teams are the same way, they work with some fixated budget and if a player had relly good season he becomes too expensive for them to sign without breaking the structure of their budget. Same way, if a player disappointed he will probably move to be a star player in a different, slightly lower-level league rather than resign with the same team for the lower price tag. Those are the general rules of thumb in the cobweb of mid-tier leagues.
There are some exceptions to that but those are fairly rare and mostly at the bit higher (at least EBEL) level. Below that, 99% of the legios will just go year-to-year.
P.S. Also, isn't it better to just link your profile instead of extensive write-up? It takes like 2 minutes to find it. There really aren't many 6'5" dual-national Ds in the CIS, not to mention higgi21 is a fairly transparent nickname.
To put it bluntly, your European hockey journey will be really tough if you decide to go through with it and you won't be making much money. Very unlikely you will ever reach NLA, snowflake chance in hell kind of probability. It also seems unlikely you will accumulate any significant savings during your career. I would only suggest you take this path if 1) you absolutely want to experience the livelihood of pro hockey player and are ready to be an adventurous journeyman; 2) you want to tie your future to Switzerland/Europe rather than Canada/Noth America for some reason.
Most of the stuff I or people here have written doesn't really apply in your situation. You need to either look for options in SLR (3rd tier Swiss league) or other bottom-tier European leagues. But having Swiss citizenship SLR seems like a better option, obviously. Having said that, almostawake made an excellent comparison, your salary would be roughly that of a McDonald's employee in any of those places. Only choose this path if you absolutely want to try it or you are absolutely sure you can make it to the next level. In any case, this is a big risk to take.
By using the eliteprospects link you can find players who have gone through something similar, Jason Seed, for example, had a rather similar path. He is now playing in a small Polish mountain resort probably being paid ~12k euros (after taxes) per season with car and rent taken care of (usual practice). And keep in mind he had to spend two years in French 2nd league just to get there. So some might see him as the guy who made it, some might see him as the guy who wasted 15 years of his life by chasing hockey dream. It all depends.