Wish you all the best, I think the car you are buying is one of the best on sale at the moment.
There is a strong message in this for Maserati. Many of us on here keep coming back for more - I for one have had three Masers over the last 15 years and have done something like 80,000 miles in them - but the market is not that kind in the main. Most people with money will buy a half dozen car brands and will chop and change between them as it suits depending on the timing of product life cycles and the tech offered in cars. Maserati is weak in both counts in that it changes it's shapes very infrequently and the tech is always verging on last generation or last+1 in the case of my car. I really can't see how Maserati will survive if it does not address these issues. At the moment my money is on Alfa not Maserati.
Having switched to an Aston, you make an interesting point.
Aston have had the Vantage and the DB9 for 11 and 12 years respectively. Quite long by most manufacturers standards. But similar to Maserati. However, from what I've seen and read in the Aston owner's and enthusiasts world, people do not seem to feel that there is a lack of choice or progression.
Aston evolved the Vantage over the 10 years: the Vantage, Vantage S, Vantage V12, Vantage V12 S, GT12 and GT8 - along with a number of Special Editions over the years. This has kept interest and given people things to upgrade to.
With the DB9 they have done similar to the above with the evolution of the DB9, but even more by creating the DBS.
Maserati seemed to have failed on having variations of the GT over the years. Yes there has been GT, GTS and Stradale, differing gearboxes, along with interior and exterior updates. But I don't feel it has presented enough options.
I also feel they could have made MUCH more of the Strad, like Aston did with a Vanquish. Made it that bit different so it forms its own separate product line, rather than being another type of Granturismo. If they couldn't up the engine size to a V10 or V12 (possibly due to Ferrari crossover) then turbo charge it, or at least try and squeeze more displacement out of the V8.