I've been "sort of" looking at this on and off to see what's out there, partly because we need to upgrade the lighting at church, partly because I fancy something different at home.
The big issue as I see it is not getting locked into some proprietary system - and DALI ticks that box. BTW AIUI DALI does not need a central control unit - though you can have one if you want. Unlike DMX (which is the faster system commonly used in theatrical type setups), DALI can have multiple controllers on a bus - so for example, you can have a DALI module at a light switch, and program it to send on-off messages direct to a specific bus address so it works the light in that room. Even two (or more) way switching shoudl be easy to do with stand alone controllers - pressing "on" on any of them will signal the light to turn on, pressing "off" on any of them would signal it to turn off.
You can also have a centralised system that will (for example) turn lights on/off at different times during the evening to make the house look a little occupied - and if it controls the same light as the switch, then the light will follow the last instruction it receives.
Gets a bit more complicated if you want (e.g.) security lighting with PIRs and stuff, as then you might need a centralised controller to manage inputs from the PIR and manual switches. You wouldn't want to switch the light one with the switch, only for the PIR to turn it off as normal a few minute after you've walked past it.
As for wired vs wireless - give me wired any day. Wireless has all sorts of interesting failure modes, depending on how things are set up. If you don't connect them to one network then it's going to be an interesting setup to manage; if you do then you make things dependent on that network (when your internet router goes down, all your lights stop working, sort of stuff). And if your wireless kit isn't "robust" in it's protocols (in particular getting acknowledgement of each transmission) then it won't take much interference (including other band users) to cause lost messages.
The one downside of (e.g.) a DALI bus is that one faulty device could block the whole bus - but then one faulty device in a traditional setup can "block" a whole circuit by tripping/preventing reset of the MCB or RCD.