Based on the specs on Roland's website, the EX30 has no filter, envelope, and DSP effects other than reverb and chorus. No mention of arpeggios and sampling, either.
Even the PSR-740, based on when I checked the manual, does not have filter and envelope.
Also, the PSR-E463 has harmony effects, but some of those are echo and tremolo -- which are not dependent on the chord being played and whether auto-accompaniment is on or not -- and these effects can add a delay-like quality to a sound. Does the Roland have these? Again, not sure -- not mentioned on the website.
The specs of the Roland on their website do not mention registrations, splitting the keyboard, or layering the sounds. Maybe it has these features, but they are not listed on the website. The combination of filter, envelope, DSP, combining 2 sounds (main and dual), and splitting the keyboard -- along with the ability to easily save these settings in a registration -- give the PSR-E463 synthesizer-like qualities at a bargain keyboard price. Indeed, the ability to combine 2 sounds, with each having their own filter, envelope, volume, and octave settings, gives the PSR-E463 much of the same sound control that you would see on a dual-VCO analog synthesizer, and the live-control knobs make it easier to zero-in on the sound you're looking for.
And let's not forget about the onboard 6-track sequencer. The Roland site does mention the ability to record songs, but it does not say if tracks can be layered or not.
The PSR-E463 is not just for beginners. I have played keyboard for 43 years, and I have owned a PSR-E433 (one of the E463's predecessors) for over seven years.
I will admit that I would like to see a few updates to this series, such as individual A/B style parts and fills -- or at least a dedicated fill button that does not switch the A/B part, some basic editing for the sequencer, and the ability to set the sustain pedal to control both sides of a split keyboard and not just the right/upper side. But Yamaha has yet to add these features, so I have kept my PSR-E433. But the PSR-E463 offers an incredible array of features and effects, especially for the price.
Of course, this is not a criticism of Roland, themselves, as I also own a Roland Gaia SH-01 synthesizer.