I'm not entirely sure what the issue you are having with Event Hubs is, but I can answer your questions about Event Grid.
Can it connect to Event Hub?
Yes, a Hub is a valid destination: https://learn.microsoft.com/en-us/azure/event-grid/custom-event-to-eventhub
Does it offer the same features as Service Bus?
Kind of. It does use topics and subscriptions, so it is similar to Service Bus that way. Where it differs is in how messages are delivered. Service Bus uses a pub-sub model where clients request messages from Service Bus. Event Grid uses an event model where it pushes messages out to each subscription by sending a message over http. If your question about intervals is whether you can build up messages and request them all at once, then no, that is not how Event Grid works. It does have a retry system but I would not want to rely on that for grouping messages together if that is what you are trying to do.