Batch handling - is actually "prefetch" in RabbitMQ/AMQP. Error reporting - via logging, and a "dead letter mailbox" (called a dead-letter-exchange in RabbitMQ) which is a great enterprise integration pattern for properly handling errors and retries in jobs.
RabbitMQ does the heavy lifting in another surprising facet - the UI. The management UI is excellent and at some point in time I decided not to compete with it by creating my own UI (you have to pick your fights :).
Here's some more info about the management plugin for RabbitMQ.
I suspect that if this project takes off someone will put together a front end that mirrors Sidekiq's in short order.
I do wonder how this one would work out though, will have to give it a try at some point.
Discussing reliability - this is something that sadly Sidekiq will never give you, by virtue of the fact that it uses Redis. RabbitMQ can be clustered in active-active mode, which means you have won over reliability here by just using a cluster.
When comparing queue systems, comparing Sidekiq+Redis to RabbitMQ is a bit unfair - because RabbitMQ was born to do this. And that's why if you're doing proper background jobs and messaging it's better to pick the right tool.
That being said, I do keep using Sidekiq for small Rails apps for the typical background emailers, denormalizers, etc. But I keep an eye open for when I realize that I'm doing proper messaging - in which case I'll switch over to something like Sneakers.
Redis Clustering tutorial: http://redis.io/topics/cluster-tutorial
Redis persistence (using AOF or RDB or both): http://redis.io/topics/persistence
Even though it doesn't have clustering - it's rock solid in production and I haven't experienced a drop in one of my Redis servers in around 3 years.
That being said, if you are building a system where reliability is an explicit requirement you can't take those risks.
i would start here: http://aphyr.com/tags/Redis
However, what was your concurrency level set at? I know when I've set it to one, I've had good success with the most demanding tasks. You essentially lose the threaded benefit, but keep the other benefits.
At least, as reliable as you can get with Redis...
Without having looked at it yet, how does the pre-built UI compare? From an initial glance, it looks like anything that's missing is available via the DSL, but Sidekiq gave me so much of what I needed out of the box (having come from a custom-made solution using SQS + open source CFML) it made my head explode.