As a scanner user that has no need for a pager, my primary reason for purchasing a G4 is to have a fairly solid solution to listen to P25 Phase 1 (and possibly in the future Phase 2) simulcast systems (as a hobby - not for work). Before my purchase and based a whole lot on being "burned" to some degree with Uniden's glossy pre-sale promises for their current line of flagship scanners, I did my homework to determine in advance that this radio would do what I was expecting before I bought it.
It is unclear what you believe you need this radio for (you really didn't say other than you're trying to justify the cost to someone else so they can pay for it).
If all you really need is VHF or UHF two-tone paging/alerting, then the G4/G5 is overkill. You might feel you need it (or want it) but from a business standpoint, those who pay the bills may not so it the same way. Again, I don't know your situation so I cannot say that with any certainty.
As far as how it works, in terms of monitoring, you can monitor one of more conventional frequency/channels (monitor or silent until tone out) or you can monitor talkgroups on a trunked P25 system (to include as I understand it, for tones). However, you have to choose - scan conventional channels or monitor a (one) trunked system - you can't do both simultaneously - and you can't monitor more than one trunked system at a time. To be clear - it handles P25 control channel systems - not older Motorola systems that have a mix of analog and P25 digital voice.
The radio can always record but you can program it to not record - by talkgroup/channel and/or entire groups of talkgroups/channels.
The programming software does have a Push To Listen option for each group of things which I assume, under the correct programming, does something similar to Minitor pagers.
What "standard features" do you believe aren't on this pager?
As far as being a pager vs. a scanner - clearly they developed a series of pagers for a specific audience. From everything I've read, they never even considered a scanner user market - at least not until scanner users saw the potential of the pagers. They have a market they are trying to serve and need to address issues in that market as a priority over hobby scanner users desires to have things added that were not in their roadmap. The have to support the promises made to existing customers. It makes business sense.
Only the company developing a given capability can tell you what is on their development roadmap/plans and where any additional (new) requests appear or will be inserted on that list. They'll work on where they believe their market (and the money) is. And just like other vendors, they'll keep that close hold because people are far to quick to react to the belief that a feature or capability is coming only to have it delayed/deferred in favor of other features deemed more important or critical to their market base. Sure, they could unlimited resources (people, dollars, etc.) to adding features but only if you the consumer are willing to spend unlimited resources from your hard-earned dollars to pay for it (you won't so they can't).
Should they try to force what started as a pager to be a scanner? In my opinion, probably not. We'd all probably end up being unhappy with how it works because they forced it to be something it was not designed to be.
Could they try to satisfy their hobby scanner user market with another unit? Maybe. But they'll only do that if the financial benefit to the company's bottom line can be seen before going down that road.
Frankly, I think I'd prefer to see the existing scanner vendors produce a new product that starts as a scanner (because that is what is intended to be from the start), receives simulcast (and distant) systems as well as the G4/G5 do, and reuses all of the existing capabilities of scanners that they've already spent years developing. They have the best shot at a scanner like this because they have the history and large code bases of software functionality now. Hopefully, they see the market demand and will (or are?) working in this direction already -- only time will tell.