Contabo on shared Litespeed for twenty-five bucks? That's already pushing it with ten sites, unless they're all tiny. Hetzner's Ryzen nodes in EU used to choke on concurrent builds in my experience. OVHcloud felt snappier but their ticket queue was rough last winter.
VPS with Hestia or aaPanel isn't as scary as it looks. One afternoon of setup, then it mostly runs itself. But if you're dead set against it, maybe check whether those mystery providers you tried are overselling their Litespeed workers. That's the real bottleneck people miss.
What kind of traffic are we talking? Static brochure stuff or dynamic...