Have I missed any important criteria?
One of the best features of the Rigol is that it can be remotely programmed and I think that this would be the only reason I would want the Rigol on my bench.
Otherwise I don't see anything I like about this PSU. I guess we all have different opinions on what makes a good PSU but here's a few things I don't like about the Rigol 832.
The display is too small and cramped and the VA info is not above the relevant PSU output. I don't want to be looking at a tiny cramped and offset display.
It looks like you have to manually select control for each PSU by pressing a button to enable each in turn. I would not like this. It's bad enough having to look at the cramped and fussy display but to have to move my hands across several buttons just to trim each PSU supply manually would drive me mad. I'm used to old school supplies with touchy feely controls and big displays for voltage and current that you can see from across the room at a glance.
One minor gripe is that there is only one 4mm socket per terminal. I've kind of grown up using TTI supplies where you get the extra 4mm socket for the sense connection and this makes life easy when making multiple connections.
In the UK it costs about £320 so it scores very highly (in terms of bang per buck) for the fact that it is remotely programmable but I don't see much else to like when compared to buying a nearly new TTI PSU for a fraction of the price.
It's not really realistic to have a separate keypad for each channel, so if you get a keypad and multiple channels, you'll always need to have a way to identify which channel you're setting.
Having the display for the channel be directly above the connections is a non-issue, IMO... the display matches 1-2-3 left to right, same as the terminal layout - and the fact that you always have test leads going from the PSU to whatever you're powering already abstracts the display from whatever is connected anyway.
I also am a bit shocked anyone would say the display is cramped and small - one of the things I like about the 832 is the display is big and really easy to instantly see what's going on. Maybe there are PSU's out there with 10" LCD's on them that I'm not aware of, but coming from single line LCD or dual line VFD PSU's like my Philips/Fluke/Agilents, I find the 832 to have a huge and really clear display.
I don't think TTI makes any models with more than 2 displays, so if you get one of their triple output units that matches channels with the DP832, there must be a switch to change what one of the displays is showing, or that output has no display. I also don't see anything but volts/amps on the TTI's... so setting any of the dozens of features that the DP832 has must either be a chore, or those features don't exist on the TTI (which I think is the case) - stuff like OCP/OVP, tracking, timing, analysis, saving configs, etc.
Not to mention 3-channel TTI is, what, about double or triple the price? Does the TTI have LAN/USB/RS-232, etc?