Changes made via the Hue Bridge (including other third-party integrations like ST and HE, as well as the Hue Alexa integration), not just changes made via the Hue app, are reflected immediately in the Hue API. Hubitat would get those at the next poll, even if it's been less than a minute (which I think is the default interval, but it is marked as recommended in either case). I'm not sure what you mean here. The only time I've seen Hue not always show the right status is when a bulb is directly manipulated via TouchLink (e.g., a dimmer-style remote or similar device) or sometimes when at the API level a bri_inc command is issued and then stopped, and the device takes about half a minute or so to figure out its new bri value.
I agree with @SmartHomePrimer -- I like using groups in Hue rather than Hubitat and doing third-party integrations like Alexa through Hue instead, with the drawbacks he mentioned. Another advantage is that Hue takes care of things like Zigbee group broacasting for you behind the scenes, something Hubitat can't do over the LAN (how the Bridge integration works). A group or scene in Hubitat will send individual commands to each bulb, so they'll respond in series and create an effect some people call "popcorn" for that reason (may or may not be noticeable all the time); a Hue Bridge group or scene will send a single command that all bulbs receive at more or less the same time and make the appropriate change, which in my experience is faster (I almost typed "more reliable," but that's not really true for the LAN-based integration, which is good; it is true compared to Zigbee bulbs paired directly to Hubitat, in my opinion, which require care even if you follow the guidelines).
Did you add any lights or just groups? I don't think it's supposed to work this way, but some users have reported that groups don't work for them in Hubitat's stock Hue Bridge integration unless they add at least one light.
In related news, I developed a third-party Hue integration for Hubitat called CoCoHue. If you're totally new to Hubitat, I'm not sure I'd recommend custom code at this point, but if you are interested, it supports Hue scenes (you'll still have to wait for the next Bridge poll for light states to be updated) and can work with only groups and no individual lights/bulbs (I don't think that's intentional in Hubitat's own, though). It also supports a few other features lacking in the official integration, like startLevelChange and stopLevelChange commands on groups (for smooth dimming, useful for a "dim while held" effect with button devices; Hubitat's supports this only on individual bulbs). Just something else to consider!
