Nice to hear you've been enjoying iZombie! The majority of the shows I've watched have gone downhill with each season (Teen Wolf... OUAT... what can I even say about those trainwrecks. Even LOST which is still my favorite ever had a significantly weaker season 6), so it's good to know some shows develop for the better at least!
The comedy/drama thing sounds really good in theory but I think for me iZombie just doesn't seem (based on the little I've watched) quite funny enough to be watched for the humour, or dramatic enough to be watched for the big emotional impact. But if the mix is right I do like it, a great example would be Farscape where some of the episodes were super tongue on cheek and some were super emotional. That was another show that developed for the better, I think!