You may find this link useful.
Although it is UK based (I am not sure where you are), there it is a really useful read.
https://www.food.gov...-and-discussion
It is important to consider the differences between validation and verification, of which the BRCGS Standard requires both.
What you have described this far are examples of verification. It is perfectly acceptable to undertake tests internally, such as visual inspection, protien swabs, ATP and specific allergen swabs. You could also undertake swabbing on a routine basis and send to lab for testing. You will also do things like internal audits. That is all verifying the systems you have introduced are effective.
Validation is something that generally you only do once (repeated for any significant changes) which proves it will be effective. Examples of this would be information from your cleaning chemical provider that the product has been validated to remove X allergen following Y method.
Another example would be conducting your own allergen tests which you may do after your first run - you map the process, identify highest risk points and swab those following clean to show the cleaning method you have used will be effective at removing the allergen you are considering.