Zabbix is a great solution when we talking about working with a problems
We're able to create alerts in many ways, but... All of it is limited by Zabbix only.
We have to create items, triggers, make some workarounds with zabbix_sender utility and sender protocol to make Zabbix looks like an Umbrella Solution because Zabbix could be not the only system, which generates alerts and it would be a great benefit for Zabbix to use it as a Unified window for all those systems
So, Zabbix should have a possibility of generating problems which are not related to any item or trigger.
A new API method could be a solution here, like event.create
Possibility of 3rdparty problems receiving/generating open new opportunities like - internal synthetic problems generation in Zabbix (Button - generate a new event for a trigger could save a huge amount of time), correlation-related new events, etc...
So, please, consider this suggestion for implementation in the next releases