Another happy Week Cal user -- first on the iPhone, and now also on my mini when they (re-)released the iPad version.
I tried the Readdle app a while back (before Week Cal HD was available); it seemed to be a pretty solid product, with good support. But I had grown to like the Week Cal functionality, so when the iPad version became available I snatched it up.
I got LifeTopix a couple of weeks ago. I mainly wanted a way to make notes on calenders (this came to me after I lay awake until 2am one morning for no apparent reason).
It also lets me put todos that I can actually check off. It's probably way more full featured than you are looking for, but it does integrate with the stock calendar and syncs across my devices, alarms and all.
What I really want is a mix of a calendar, Things and Notability. Then my digital life will be complete