No problem to answer more questions!

Beach and surroundings are much better at the FS Seychelles compared to the FS Mauritius!

FS Mauritius is located within a lagoon and though the setting is quite spectacular with high mountains behind the resort, this location does not come close to the stunning location of the FS Seychelles. The beach(es) at FS Mauritius are all man made and there is no snorkelling off the beach while the beach at FS Seychelles is a real gem with powder soft sand and great snorkelling just off the beach (manta rays and sea turtles seen several times in addition to lots of fish - not as good at snorkelling in the Maldives, but still very good). Also the possibility to see more beautiful nature outside the FS resort is better at the Seychelles, with lots of beaches, rocks, jungle etc. to explore.

Also the villas at the FS Seychelles are significantly better than the villas at FS Mauritius.

However, Mauritius wins 10-1 when it comes to service. It cannot be compared at all. There has been significant work done at the FS Seychelles to improve this (lots of staff from other FS has been there to help according to senior management), so it might be better now than a year ago when we were there. While the service issues we experienced at the Seychelles did not ruin our holidays, it was disturbing at some times, and the amazing service we experienced this time in Mauritius really made a difference in terms of giving us a totally relaxing and worry free holiday.

Last but not least, the food was better at Mauritius, so where to go, really depends on what is most important to you.

(Maldives have great beaches if you go to FS LG and good service + nice villas at both FS resorts, but the experience is more comparable between Mauritius and Seychelles since these two has more varied nature, not just sand banks and palm trees.)

You can, however, have beautiful beaches, ocean views etc. at Mauritius, for example at Le Toussrok and O&O St. Geran. I have been talking only specifically about the FS.

Regarding prices:
For this time of year, the prices in Mauritius are higher than the prices at the Seychelles, so I do not understand your question.

Weather:
I was really worried before going there, reading about 22 degrees celcius since I really love the typical tropical climate with 30 degrees. The first two days it was also that "cold" (still spring) and together with the sometimes very strong wind at the east cost where FS is, it was comfortable in the sun during daytime but too cold for my liking to sit out at at night (not in the restaurants where there is no wind, but outside the villa) at a bit coldish in the early morning.
However, the summer came on our fourth day and we had around 26 degrees which was great. Still a bit chilly at night, but not so that it would put me off going back, even if I surely prefer the normal tropical climate. I would, however, rather go late October than early October to be sure to have 26 rather than 22 degrees.