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- The fact that the Lead Description field goes to Contact Description - Really? Why? The whole point of the Lead is the widgets you are trying to sell, so you need to capture details of those widgets first and foremost. See above for how to fix it.
- Primary Campaign Name not visible on the page - see https://success.salesforce.com/ideaView?id=08730000000Bq5wAAC
- You can't set the checkbox on Lead Conversion to default to DO NOT CREATE OPPORTUNITY - use this trick http://help.salesforce.com/HTViewSolution?id=000213337&language=en_US
- Chatter posts don't convert along with the Lead - See Lead Convert Chatter on the Appexchange.
- You can't convert to a specific Record Type on Account or Opportunity, only the default record type of that user - STUPID! Do this https://help.salesforce.com/apex/HTViewSolution?id=000004455&language=en_US
- You can't map one field to multiple fields (eg a field on Account and Opp) - create another field and update it by workflow.
- You can't convert from a formula to a value - that would be handy.
Weird Things
- Who knew you could convert Leads multiple times? Well if you have Modify Audit Fields permission turned on, you can - the Leads never appear Converted, even though IsConverted=true. Use with caution. With Great Power comes Great Responsibility! https://help.salesforce.com/apex/HTViewSolution?urlname=Leads-are-able-to-be-converted-multiple-times&language=en_US
Sample Layout
After the lead has been set up with the client's fields, it will look something like this. Note the different sections that are clearly identifying what this lead record is about. Some orgs may want the Lead Information up the top.
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