I think that using an ORM is still a good idea. Especially considering the situation you give. It sounds by your post you are the more experienced when it comes to the db access strategies, and I would bring up using an ORM.
There is no argument for #1 as copying and pasting queries and hardcoding in text gives no flexibility, and for #2 most orm's will wrap the original exception, will allow tracing the queries generated, etc, so debugging isnt rocket science either.
As for validation, using an ORM will also usually allow much easier time developing validation strategies, on top of any built in validation.
Writing your own framework can be laborious, and often things get missed.
EDIT: I wanted to make one more point. If your company adopts an ORM strategy, that further enhances its value, as you will develop guidelines and practices for using and implementing and everyone will further enhance their knowledge of the framework chosen, mitigating one of the issues you brought up. Also, you will learn what works and what doesnt when situations arise, and in the end it will save lots of time and effort.