Best Nani Build for non-heist

Nani is a great sniper with consistent damage, interesting attack patterns, and very strong Gadgets and Star Powers. I frequently pick Nani as a counterpick against other snipers in maps that are somewhat open. Be wary of picking Nani against other high-range, multiple projectile brawlers such as Colt.GadgetsAgainst other snipers, Return to Sender is almost always the best option. It allows you to win any Sniper 1v1, provided you have good enough reflexes to activate the gadget in time. I occasionally use gadget, then purposefully walk into attacks to prevent them from healing in modes where it's more relevant. An important interaction is that against turrets, this will not harm the brawler. Ex. Penny's turret or Tick's Head will not damage Penny or Tick if the damage is reflected.
Warp could be considered for Heist or Showdown, but I have less experience with Nani in those modes.Star PowersNani's Tempered Steel shield is very significant, making you practically invincible during the duration of your super. I occasionally use this very similarly to Return to Sender: Just before being hit by an attack to survive. This does charge their super and hypercharge, so this should be used cautiously against certain matchups. It's usually better to use it while within a Hot Zone or to make an opponent waste ammo in KO or Bounty. Or against assassins, using it quickly after they jump/appear will keep you alive at fairly high health and give you a good position to defeat them afterwards.
The other SP is still useful, sometimes better in KO or Bounty to kill snipers who've already taken some damage. This enables a more passive playstyle and should be used at your own discretion seeing the matchup, mode and teammates. GadgetsI've never seen the Super Charge Rate Gadget do anything, so would avoid it entirely. While I could see some arguments for most of the others, Shield + Damage seem the best. This lets you defeat assassins without Tempered Steel by spamming the auto-aim, usually defeating the opponent before you. Shield works well with Tempered Steel because opponents need to deal a total of 4,500 damage to even get through a max 900-health shield. It's fairly common for the shield's regeneration to outpace damage dealt.