If you want Motorola trunking then IntelliRepeater is your answer.
for many reasons.
1. No controller is needed because the IR is in itself a controller without certain bells and whistles {that only Public safety really need so who cares about that}
2. The IR option can be set as "Voice on Control" meaning your control channel and voice channel are the same. And yes this works very well. I should know, I am currently using it! This option would be very helpful on VHF where finding 1 frequ. pair is difficult and in some areas impossible. So this would give current repeater owners a way to switch without the hardship of finding more pairs.
NOTE: If using {VOC} disable Failsoft. Otherwise your key up requests will be delayed and transmissions will be lost.
3. Station ID can be broadcasted on the same channel as control. So no problem there. Just make sure to keep the ID short because this will cut into your Key up times.
4. User call sign IDing {If you are using more then one trunking channel} is simple. Just enable "soft ID" on your radio and input your call sign. You will then be transmitting your call sign each time you transmit so that solves that problem...
5. Since IR trunking is part of a SmartZone system you get the cool signal strength antenna bars in your radios
6. Private call. You can individually call another ham without disturbing the rest of the group ! And still legal because there is nothing encrypted. Although I been told that you can do encryption on ham just call it "Authentication" But that is another subject all in itself that wont be discussed here

7. The station can be programmed for mixed mode trunking if you wish to do so.
I personally would not put up a 900MHz trunking system because of the poor coverage and voice quality. I rather do UHF or VHF
I personally would like to see a Nationwide Ham Trunking Network. Or at least have the same system ID on each repeater so your radio automatically logs into the closest trunking site eliminating the need to buy ARRL repeater books ! Just have a set of national control channels and talkgroups. Linking and simulcasting is obviously more difficult and costly but we can at least start setting up single site stand alone systems and worrying about linking them down the road when the ground is already laid out.
This could work if enough people got together. But I can not do it alone.
If anyone wants to set up anything like the above and need some help PM me.
I also currently have systems on commercial {trunking and non-trunking} that me and a group of guys play with. You can say we are tired of the same ole crap on ham. Which is why we migrated to commercial. So if anyone out there has a commercial system they want to link with ours PM me on that too. We are always looking for people with the same interest.
But I am all for giving ham a face lift if others will join in and help out.