Yes and yes.
For some reason Triumph have put very low spec suspension on the entire model run of Sprints. I was hoping, even expecting that adjustable suspension would have at least been an option for the 05+, but no.....
There are many things that can and have been done by many owners. It just depends on your budget and riding style. Suffice to say anything you do that improves the suspension in one area will bring a noticeable improvement and also show up deficiencies somewhere else.
Search here and other forums, there is heaps of stuff already documented.