What is right for you, is not necessarily right for someone else.
While I see the merits in a LA, I know my back would not be too appreciative.
I came very close last spring to purchasing a S16 ... and did not.
Yes ... a DSM with larger throat and all the other features will let you do lots of FMQing, though it will not have the higher stance and clearance of an S16 or similar model.
Yes ... it would sit idle while doing any other stitching, and that was one reason I did not purchase it.
In hindsight, I could have stitched quite happily on my old machine for many years to come ... and purchased the S16 for about the same as I paid for the new.
I do really really like my new machine and have done lots of FMQing ... but yes, I still lust over a sit-down S16 or a similar one of another brand. Maybe someday?
Go out and test drive all the machines you are considering.
Compare the features/benefits of all ... and decide what is right for YOU!