Hello,
I suggest you to create a copy of standard Marketing Professional role, one for manager and other for sales exec.. Also assign different custom role config key to the newly created business role. Now you can define what all workcenter is required for manager in the your custom manager business role and deactivate whichever is not required, similarly do for sales exec.
The role config key can be used to differentiate how a particular view will be displayed to different type of user, in your case they are manager and sales executives hence you need 2 role config keys.
You need to create a separate config for each view where you want the difference in visibility for them and while creating the config you have to assign the correct role config key and then adjust/assign the layout or fields in that view.
Once you have 2 different config for same view with different config keys the users logged in with respective business role will see that particular view unlike the other.
You can refer the component / view: BP_HEAD/AccountDetails and check some of the standard configuration done for different role config keys, I have attached one snapshot below which might be of some help.
Rgds,
Shobhit