There is no way in Analytics Ui to get the Processing or VISTA rule names. You may contact Customer Care to identify the rules.

You may use custom link tracking.<a href="#" onclick="s.linkTrackVars='eVar1';s.eVar1= url; // You need to write script to save the last part of url heres.tl(this,'d','Download');s.manageVars('clearVars',s.linkTrackVars,1);">Download</a>

Line graph allows max 25 line items. So, it will not be possible to create graph with all 59K plus items. To create a line graph, you need to select the line items (using shift + click) > Right Click > Visualize > Line.

Data Warehouse does not have preset beyond last month. You would need to use custom date range.

Try creating a Custom Date Range such as this: 

250 evars is still a large number, and I haven't companies run out of evars. Perhaps, you would need to review how you are allocating your evars.If you can share an example of what data you are passing in the context data variable and how you are using the values to set up the evars, it may give us ...

As per your example, the report should show Page A, right?If yes, You may run Entry Pages report with a segment Visit Number = 1.Let me know if that works. 

Intelligent Alerts in Adobe Analytics allow you to set up an alert based on certain thresholds/anomaly. See this video: https://docs.adobe.com/content/help/en/analytics-learn/tutorials/data-science/intelligent-alerts.html.

This will require reviewing the access of the users to the IO integration. I will advise reaching out to Customer Care.

Is you are referring to Visit definition, 30 min is still the standard duration. You may use Virtual Report Suites to change the visit definition.