well it all boils down to how you use your car.
DPFs are meant to work efficiently if you travel on long distances, the idea being that your exhausts are hot for longer time, so when the DPF starts the regen process it's something that happens quickly and with no problems. If, like me, you use the car for small daily journeys, then the DPF can turn into a trouble.
Most serious remappers will offer a combined package made of DPF/EGR removal and a remapping that is 1) meant to stop the car from starting the regen process and letting her "forget" about the DPF 2) to fix some of the known original mapping bugs (i.e. turbo lag).
Angel tuning offers a quality service for a competitive price, but there are others all around the UK too. Once again, if you decide to go down that route you will see an improvement of the car overall, but you have to keep into account that although tempting, a remap that gives you more torque and HP might give more strain to your flywheel and clutch, so I would recommend it only once you get more familiar with your car. There's no haste in doing these modifications if the car doesn't give you the typical symptoms. Obviously there are also more moderate remaps, but overall you'll get a definitely improved response and to a certain extent a better mpg (although you'll be even more prone to floor it, so again it's down to your common sense
Going back to the water pump, there have been cases of failures unfortunately, which end up with a hefty bill. As far as I know the recommended change by Alfa is at 90k miles, but many recommend to do it way before that (around 65k). The problem is that these water pumps don't give warnings, they just go, so if you know you had a new one when the cambelt was done that would be a good peace of mind.
And once again, get acquainted with the car, I don't know if you had Alfas before, but you'll soon see how temperamental and "alive" they feel. Learn its quirks, then once you know what you like or don't like you can start looking into modding it.
Again, this is my humble 2p, I'm sure others here will chip in
Make sure you check the steering fluid though, that shouldn't be procrastinated, esp if you have weird sounds coming from your steering box.