I used to own a Roberts 45 Classic ketch, which is very similar to your Mauritius 45. Main difference is probably the keel (mine was full where your's is probably separate keel and skeg) and mine was fibreglass so a bit lighter, around 14 tonne. So probably very similar performance.
My rig was also similar in furling genoa, main and mizzen however my inner forestay was fixed and I had a staysail (as well as a storm jib) so would probably be described as cutter / ketch.
In nearly all conditions I would not start reefing anything below 15-18 knots. Above 15-18 knots I would first put a reef in the main.
Above 20-22 knots it depends on which way you are heading. If I was heading upwind I would tend to furl the genoa 2-3 feet, unless I believed the wind was going to keep increasing. If I thought it would be above 25 knots I would fully reef the genoa and switch to the staysail on the inner forestay. I have used this combination up to 35 knots going upwind (with the engine chugging along at 1,500rpm in the last part to improve pointing and get into Bunbury harbour) and the boat felt nicely balanced. Plenty of water over the bow, however my old yacht had a pilothouse so it was'nt an issue.
Going downwind above 20-22 knots I would tend to get rid of the main and just use the genoa, and start furling the genoa above 25 knots. Above 30 knots I would fully furl the genoa and just use the staysail. Going downwind I use to often "wing and wing" the partially fueled genoa and the staysail, especially if I had already gotten rid of the main. Meant that the boat was more balanced plus it meant going forward in lighter breezes to hoist the staysail. Again I have carried just the staysail downwind in 35-40 knots and apart from one instance when the fitting blew apart on a jibe no problem (next time I would probably "tack" the boat in 40 knots rather than "jibe"
Note that I have not mentioned the mizzen and in the 5 years I owned the Roberts we rarely used the mizzen. In broad reaches it would add a couple of knots to the boat speed, however above 15 konts of wind the yacht would be doing hull speed with genoa and main, hence hoisting the mizzen was'nt neccessary. Note that the mizzen really worked well by itself when heaving-too.
With regard to the storm jib, we never took it out of the bag. I guess above 40 knots you would look at the storm jib, however above this windspeed going upwind you would not be making any progress without the engine and I would probably be looking at heaving-too in those conditions. Going downwind above 40 knots you may want some sail to help balance the boat, however you would probably be doing hull speed with a bare rig. If you were broad reaching above 40 knots I would probably be looking at a double or tripple reefed main.
Hope this helps. Below is a photo of one of the few times just about "everything" was up, around 10-12 knots broad reach on the way out to the Abrolhos Islands.
Have fun with your Mauritius.