We don't want to be perceived as cheap, but super expensive isn't our plan either. We're free for companies below $10K MRR, then charge on subscriber volumes. We can offer custom pricing to high-volume/low-margin businesses, feel free to reach out if you'd like to discuss nick [at] chartmogul.com
We're planning to add forecasting to our SaaS analytics product (https://chartmogul.com) later this year, I'm going to look and see if we can use this in our product now.
One important thing LTV misses is payback period. E.g. due to very low churn your LTV could potentially be huge but the value would take many years to realise, depending on your cash reserves CAC spending well below LTV still may not be economical if it takes too long to realise the ROI.