The Schengen rule is simple on paper: apply to the country where you will spend the most nights, or the first country of entry if nights are equal. In practice, embassies have very different approval cultures, and choosing the right one (within the rules) can shift your odds by 20 percentage points.
France is the most lenient for first-time travellers with a clean profile. Their multi-entry policy is generous: even a 7 day trip can result in a 1 or 2 year multi-entry visa if your history supports it.
Spain and Italy are friendly to family visits and cultural travel, but stricter on freelancers and unsalaried applicants. Documentation must be airtight: notarised sponsor letters, full property paperwork, and detailed itineraries.
Germany and Netherlands are document-perfect embassies. They rarely refuse a complete file, but they refuse almost every incomplete one. Submit nothing handwritten, every translation must be certified, and every booking must be confirmed (not on hold).
Greece, Portugal and the Nordic states tend to issue single-entry visas matching exact travel dates. Good for one-off trips, less useful if you plan to travel often.
Bottom line: plan your itinerary around the embassy you want, not the other way around, as long as the country genuinely hosts the most nights of your trip.