I am new to Adobe Launch, there are many requests coming from marketing team for which i have to add multiple tags in, my question is, whether I have to be conservative adding these tags in our application? Ultimately adding more and more tags will definitely impact the homepage performance.
Are there any best practices or strategy i have to consider before i start adding all these pixels/tags in my application?
1.) Create your own set of best practices, taking inputs from your site developers and QA folks to determine how reliable and performant a particular piece of code can be. Typically sites which have had marketing capabilities before the implementation of a tag manager, would need those implemented by a developer directly on the site code (then typically tested before releasing) - so your colleagues can be a great allies here.
2.) Pixel code has tons of potentially needless fallbacks. HTML injections, 1x1 image requests, <noscript> tags,etc - and often they're all provided to the marketing team verbatim with some comments in the code stating "Do not edit anything below this line". Evaluate these with your developers and determine what is required. Pixels typically just send a few parameters over to the individual vendor, so they don't need to be over-engineered.
3.) Build an inventory of all your tags/rules. The requests for new tags/pixels are usually plentiful and have urgent deadlines - removal of these items may not have the same level of attention. Regular inventory and audit can help you keep your tag manager clean and tidy. Note: if there's a rule for a specific tag/pixel which expires 30 days from now, you could even put those into the rule name - might be easier to find later.
4.) Leverage custom code only if required. Many times the Launch UI will have some functions you can use which compile into performant, optimized code. Most of the time this is better than using a 5X nested IF statement. It also becomes an easier task to maintain for other members of your team that may not be too code-savvy. If you do have some custom code to implement, you could have a developer on your team review your proposed code (Internally, I like to refer to this as the Developer thrashing session) - but it typically also results in better code in the end which will jive better with your site.
5.) Document things. I'll be honest - I kind of miss the notes field from DTM to summarize changes, but that doesn't prevent you from adding notes in custom code, keeping notes in some ticket tracking tool just so when you revisit things 6 months later you know why you put in a particular change.