Work Item Customisation

I've been asked to look at migrating groups of users from Jira to RTC.

I'm familiar with CQ and its capabilities for creating customised workflow and forms, RTC workitems is a step backward in terms of capability (more of a stair case back).

Anyway, my thoughts are that for change management we should use ClearQuest; and feed this into RTC for including work into "projects/releases". From there we can assign activities/tasks/work items (depending on your terminology) to individuals/teams. This way we get the benefits of a mature change management solution, and a flexible and usable solution for the development teams.

However, in the absence of users willing to adopt CQ, I'm also looking at RTC, for a light weight solution for change and service desk management. So, some of the basic features that I need to be able to include are

1) dependant fields (i.e. componentA -> sub-ComponentB)
2) multiple selection list box

it would appear that in RTC (I've scanend 2.0.0.2), that we cant do this without some significnat customisation effort, or an enhancement from IBM?

Or have I missed something somewhere? If someone would care to correct me and point me at the right article/documentation even better

thanks