Directory and Reviews, basic on forums

[kmk]

I try to explore and implement solution based on forums structure. There any idea how to do it? 

I am imagine if ips can give us below:

1. Custom fields in Topic Summary. 

2. A widget that let me show List of custom fields. 

3. Ability to place the widget on specific forums and others pages. 

Why I want to use forums system to do? The idea is,

1. The forums is most developed and maintained by the company, is a point compromised that ensure our business solutions offered to members will not affected by any others reasons. 

2. The forums is core, is the main system that members to use, I would like try to keep the same structure and use of habit for members, and don't have to learn to use variety of designs and structures, will be more confortable for engagement and aceptation reasons.