Careful with the expectations, this is not a support centre.
All depends on the company organisation (several companies, multi-finacial setup, specific localisations, etc. ?) so start by evaluating or describing on each location needs and then work on your system and not vice-versa!
Even so, on my former employer we had centralised servers: not only was cheaper (less DC space, better deals for big machines than smaller ones, etc.) but also for manageability of the system. Of course I only dealt with UNIX servers so it may be not the same with Windows.
The package combination/VRC structure of Baan copes very well with these centralised setups, so you can have each of your locations working on it's own VRC path, independent of the others (just sharing whatever should be common to them).
Now, by centralising you need a good policy and workflow regarding patches. I would definitely have a test server (also used as development, so you can avoid any test layers on production) to test patches/development before applying them to production. You also need to keep track of patches and so on and have only one person (global IT manager) that can approve their installations, otherwise you'll end up with a patch mess.
From the network side, depends on how your offices are connected, those systems I mentioned had the clients connect directly to the server, no citrix was ever used.