Which size is better as well??

215/45/17
215/50/17
Thanks in advance

Any other suggestions??

Then stick with 215/45/17 to get choices for high performance tire

Can opt for gy f1a2,  ps3, Advan DB, toyo t1s, Nitto neogen since ur budget allow
All above tire are asymmetric and Threadwear below 300
That mean less noise and good grip

Change from 45 to 50 profile tyre will make the speedometer inaccurate by a lot. The 50 tyre is much bigger than 45. Best to stick to original size.
You can't compare one company rating to another company rating. Each maker have their own way of doing the test so it will not be accurate. Only can compare with the maker few patterns.

Engine rated power can't be used as comparison of speed even when the 2 cars have the same HP, still depends on many other things such as torque, weight, gearbox ratio, etc. such as KTM X-Bow is lesser HP about 20% than Evo 10 but accelerate 0-100 faster.

Makers of tyre each have their own ways of determine the threadware rating. you can compare different patterns from  a maker but you can't compare between different maker. some maker even have a threadware of 700, do you believe that tyre can outlast double than other maker threadware that didn't even half of that?