Charge for real SMTP delivery, not raw send counts (reduce waste)

Many companies pay for raw send counts yet a large fraction of those sends are never accepted or never reach the inbox, creating predictable waste and noisy cost forecasting. This is especially acute for transaction-heavy SaaS, e-commerce platforms and high-volume marketing teams—part of an addressable population of roughly 2M businesses paying about $9K ACV in email infrastructure and deliverability services today. You could build a developer-focused SMTP relay and analytics platform that bills on real SMTP delivery (for example, payment triggered on 250-OK acceptance or delivery-confirmed webhooks) instead of raw sends, bundled with SDKs, webhooks, and exporting-ready telemetry. Combine that billing primitive with real-time ML scoring that decides whether to attempt, delay or reroute a send, plus routing and retry optimizations to minimize unnecessary relay costs and provide clear ROI reporting. The market is receptive: an $18B opportunity with a Market Score of 92/100 and Revenue Potential 86/100 is shifting toward usage-based optimization and deliverability-first buying, and recent improvements in real-time ML make live decisioning practical. Buyers under margin pressure want pricing that reflects value, and a model that demonstrably reduces wasted spend should resonate—especially if you can show measurable savings (tens of percent) for early customers. To stand out you’ll need defensible tech (high-accuracy ML, carrier heuristics, ISP feedback integrations), reliable reconciliation and anti-abuse controls, and a hybrid pricing model that limits revenue leakage while proving value. Be honest about the challenges: SMTP acceptance does not guarantee inbox placement, carriers change behavior, and partnering with ISPs and building reconciliation systems will take time; if you can overcome those hurdles and demonstrate 20–40% reduction in paid waste, this could be a strong, differentiated play in a medium-competitive space.