Since his refresh mechanics on Q is untouched, his combos are not touched.
The only difference is that the long combo now takes an extra bit more finesse to execute given unpowered W only slows people now and thus can be dodged if you just mindlessly spam. That's kinda it. Oh, and you lost the shield which is imo a good thing (let's be real, previous Ryze with his 2-rune shield + Seraph + AfterShock was completely bullshit), also because you get higher MS after a 2 rune combo now, which is always nice; I like to go fast.
In fact, since E automatically bounce off/spread on first hit, lane management and combos have never been easier for Ryze, especially in teamfights where Ryze used to be outright unable to do due to his abysmal setup time.
Personally, I like this rework so far. But still, I would like Riot keep eyes on his passive and ulti, otherwise the rest is probably at their perfect state.
EDIT: Correction, i think his MS boost is now lower and not higher. Anyway, don't quote me on anything regarding his MS boost.