How can I stay on fire?

As stated here, being on fire means you are doing well, and here we see that you can be commended as an MVP for being on fire for a large portion of the time.
This answer shows that destroying non-player things gives you fire points, but what all do I get points from, and how many fire points do I need to be on fire/stay on fire?

To be on Fire, you need at least 250 fire points (fire). Your fire meter can hold infinite fire, but displays 350 as max, and you fire will decay at 5 fire per second.

Getting fire:

Eliminations

"All Heroes gain Fire based on % damage done to enemies during Eliminations (i.e. 50% damage dealt = 50 Fire)"

Deployable Eliminations

• D. Va's Mech 100 Fire
• Junkrat's Concussion Mine 1 Fire
• Junkrat's Steel Trap 1 Fire
• Junkrat's RIP-Tire 50 Fire
• Symmetra's Sentry Turret 25 Fire
• Symmetra's Teleporter 100 Fire
• Torbjorn's Turret 100 Fire
• Widowmaker's Venom Mine 25 Fire

Objectives

• Payload Escort 5 per sec

• Payload Checkpoint 55

• Capture Point Capturing 180 total

• Capture Point Checkpoint 55

• Control Point Capturing 100 total

• Control Point Checkpoint 10

On-fire Rates

Ana

• 1 fire per 5 hp healed

Bastion

• Healing 1 Fire per 5 HP healed

D. Va

• Blocking 1 Fire per 25 Damage Blocked

Genji

• UNKNOWN

Hanzo

• Recon Assist 40 Fire per Assist

Junkrat

• UNKNOWN

Lúcio

• Healing 1 Fire per 5 HP healed

McCree

• UNKNOWN

Mei

• Blocking 1 Fire per 25 Damage Blocked
• Healing 1 Fire per 5 HP healed

Mercy

• Healing 1 Fire per 5 HP healed
• Support 50 Fire per Resurrect
• Kill Assist 1 Fire per Assist?

Orisa

• Blocking 1 Fire per 25 Damage Blocked

Pharah

• UNKNOWN

Reaper

• Healing 1 Fire per 5 HP healed

Reinhardt

• Blocking 1 Fire per 25 Damage Blocked

Roadhog

• Healing 1 Fire per 5 HP healed

Soldier: 76

• Healing 1 Fire per 5 HP healed

Sombra

• UNKNOWN

Symmetra

• Support 25 Fire per Shield
• 25 Fire per Teleport

Torbjörn

• Support 25 Fire per Armor Pack used by allies
• Healing 1 Fire per 5 Turret HP healed

Tracer

• UNKNOWN

Widowmaker

• Recon Assist 40 Fire per Assist

Winston

• Blocking 1 Fire per 25 Damage Blocked

Zarya

• Blocking 1 Fire per 25 Damage Blocked

Zenyatta

• Healing 1 Fire per 5 HP healed
• Kill Assist 1 Fire per Assist?

Source Note: ?'s indicate unconfirmed stats.