Where do you want to live in Phoenix if you want to maximize your chances of getting laid and getting into relationships?
Where you choose to live in Metro Phoenix and where you choose to start interactions with women (either non-bar venues or bars) should be close to each other. Phoenix traffic is pretty bad. You don't want to live in Mesa and be dating a woman in Glendale. You don't want to live in Peoria and date someone in Chandler. It would be improbable to have those interactions start in the real world but they could happen. Additionally, these interactions can happen with swipe apps without setting the geolocation filter to a narrow range. I would recommend setting the geolocation filter to no more than 10-15 miles no matter where you live in Metro Phoenix. The traffic is too difficult otherwise. Public transportation isn't that great in Phoenix, though it has improved with light rail in some central-ish neighborhoods since the late 2000s. There are a lot of sketchy people on Phoenix's light rail, similar to the sketchy people on NYC's subways. More people commute by car in Phoenix.
If you're in your early 20s-early 40s, childless and want to date other childless people, you want to live as close as possible to Old Town Scottsdale, Tempe's Mill Avenue, or Downtown/Uptown Phoenix. Scottsdale's city limits extend far north. If you want to be closer to Old Town Scottsdale and make Old Town your main scene, I do not recommend living any further north of Shea Boulevard. If you'll be choosing Phoenix as your main area, it is best to live south of the Phoenix Mountain Preserve and north of Downtown. Phoenix areas south of Downtown are a bit sketchy, but might work you're into Latinas.
North Phoenix (north of the Phoenix Mountain Preserve within Phoenix city limits) is a difficult place to date, especially if you're 35 and under. North Phoenix doesn't have a lot of nightlife and the closest nightlife areas are Old Town Scottsdale and a few central-ish Phoenix pockets. Your logistics in North Phoenix won't work well for one night stands at Old Town or Central Phoenix type bars. Daygame and social circle game might work better in North Phoenix.
North Scottsdale (areas north of Shea Boulevard) is similar to North Phoenix, except North Scottsdale has a few more bars and a more active nightlife scene. The women in North Scottsdale nightlife venues are 35+ typically. There are some divorcees and single moms. I wouldn't recommend North Scottsdale for men under 40, even though there are some solid apartment complexes, townhomes, and condos in the area. You're well positioned for the 35+ set in North Scottsdale so this might be a viable option for a 45-60 year old man, with or without children.
Far East Valley: These are the suburbs east of Phoenix and east of Scottsdale and Tempe. This includes Mesa, Chandler, Gilbert, Queen Creek, and Apache Junction. Living out in these suburbs is difficult on your dating life. There is some nightlife in the Far East Valley. However, you're not well positioned to date people outside of this area. Lots of families in Chandler and Gilbert. Mesa is more Hispanic so a man seeking Latinas might find Mesa acceptable.
West Valley: These are west of Phoenix suburbs. This is also a hard home base for dating. There are some middle class + divorced single moms in places like Peoria and Glendale. The more southern part of West Valley is more Hispanic/Latina. Areas like Avondale, the southern half of Glendale, and Goodyear. Childless men in the West Valley trying to date childless White Phoenix/Scottsdale/Tempe women are at a major disadvantage here.
If you're 55+ and want to date women 55+, Sun City and Sun City West are ideal for that. Areas near Surprise's Sun City Grand would also work for that. I don't think that applies to most men on this forum, but plenty of divorced/widowed 55+ guys are having sex with 55+ divorced/widowed women in the Sun City retirement areas.
Most men under 45 won't be out near these areas looking to get laid. The primary reason for a man under 45 to be out in the Sun Cities would be to visit his parents or an uncle/aunt that happened to be a retiree.