Best Bowler in IPL History

Analyzing the top bowlers in IPL was twice as hard as looking into the performance of batsmen. Where only SR+Avg was enough to explore the performance of batters, Eco+Avg along with Dot% felt like a better measure to evaluate a bowler's execution of plans on the field.
Economy remains the primary parameter(barring exceptions) whereas Avg and Dot% would be the secondary, yet deciding, elements in this article.
Stand-out performers in each category are highlighted for reference. The only filter: 1000 deliveries bowled.

1. Overall:

Rashid, Narine, Steyn, Malinga & Bhuvneshwar are clearly way ahead from the rest on overall stats. Since Rashid has bowled comparatively lesser than the other 4, its safe to say that Malinga & Narine win this category hands-down.
Where Narine's intimidating economy presents a strong case, Malinga's formidable Avg of just 20 places him right up there with the Caribbean magician.

2. Powerplays

There is no better IPL bowler than Bhuvneshwar with the new ball. Although Rashid has a mind-blowing average of just 21, he has bowled just 20 overs so far, whereas Bhuvi has bowled 230 overs, most by any of the names on the graph. Not only he maintained the best economy but also has bowled a daunting 58% dots in opening overs. Truly the ace of powerplays.
Ashwin would be the 2nd best on list with Avg of just 25, getting those crucial opening wickets from the ~140 overs he has bowled so far.

3. Middle Overs

Average is the primary axis here as maintaining a good economy isn't as tough as picking wickets regularly in the middle overs when batsmen are trying to cautiously lay the foundation to go berserk in the penultimate overs. A captain wouldn't mind exceeding in excess of 8 if the bowlers are giving him breakthroughs which eventually dents the chances of opposition to go big unless they have a deep batting line-up.
Malinga has somehow managed to sneak in this territory meant for spinners where Rashid leads the pack. Chahal & Tahir are other outstanding performers. Steyn's 47% dots are also noteworthy with an economy of just 6.

4. At Death:

What won't you give to have a bowler in your franchise who can bowl as many as 47% dots in the death overs?
SRH is lucky to have Rashid who also happens to maintain the best economy in this phase of the game. Malinga with an average of just 13 negates his elevated economy. Harbhajan deserves a mention for his stupendous average of 12, which is the best in the lot.

5. On 6 Least Economical Venues

Even though the Economy stands the primary parameter in this category as well, Nehra(18) and Chahal(21) have been highlighted for their brilliant average on the most run-fishing grounds of IPL.
Malinga & Rashid, our usual stars in each category so far, haven't left an impression on these grounds whereas Bumrah makes the cut for the first time so far. Steyn makes up for his not-so-impressive average with the best economy, but the real star on these grounds will have to be Bhuvi who has done exceedingly well in all departments, followed by people's favorite-Bumrah.
Refer the Venue-wise economy below:-
Indore: 9.10
Mumbai (BS): 8.83
Kanpur: 8.73
Bengaluru: 8.56
Mohali: 8.38
Dharamsala: 8.28
Cuttack: 8.23
Delhi: 8.21
Kolkata: 8.12
Mumbai: 8.12
Ahmedabad: 8
Chennai: 7.93
Hyderabad: 7.91
Jaipur: 7.9
Pune: 7.82

6. vs Top 20 Hitters

There is only one winner here, but Bumrah and Steyn have been impressive as well. I was going to keep only SR-Dot% as the scales here but Rashid's magical average didn't allow me to do that. An average of just 14 with the best Economy vs the Top 20 hitters in IPL places him in a different tier altogether. His Dot%(47) is also second only to Steyn(50%). Refer the Top 20 batsmen with best SR in IPL's history below:-
Russell
Narine
Moeen
Rishabh
Maxwell
Morris
Bairstow
Sehwag
Hardik
de Villiers
Gayle
Buttler
Pollard
Krunal
Sanath
Ashish Reddy
Lumb
Yusuf Pathan
Sarfaraz Khan
Warner

7. vs Top 20 Anchors

Forget the top performers, look at who is topping the chart from the bottom(right in this graph). With the highest Avg of 47 and an economy of 8, Malinga has done worse against the heavyweight anchors of IPL.
Coming back to the champions of this category, only spinners have managed to keep their average(primary parameter) under 30. Chahal here is the clear choice to get big scalps. Narine and Rashid(as usual) have also done exceedingly well.
Refer the batsmen with Top 15 Batting Averages(min 2k balls) below:-
Warner
Dhoni
Gayle
de Villiers
Kohli
Sachin
Dhawan
Raina
Rahane
Rohit
Watson
Gambhir
Manish
Yusuf Pathan
Uthappa

8. While Defending

Even though Economy is the primary scale here, Avg should also have similar(if not more) weightage in the second innings.
While Narine(Avg 18+Eco 6) stands out, Rashid, Ashwin, and Malinga (Avg 20) are also brilliant in defending the runs on board.

9. Bowling 1st

Steyn is a slightly better bowler in the 1st innings who makes the cut for outstanding performers in this category. Rest of the graph remains similar to 2nd innings where Malinga again has done exceedingly well with his bowling average.
Rashid, again, is ahead from the rest, with Narine slightly worse than he is while defending.

10. The Big Stage

I have no idea what to call a bowler who averages just 11 with an economy of just 4 in the matches that matter the most. The best thing about it is that he has bowled almost the same number of balls as the rest(~20 overs), negating out the 'lesser-played' factor for Rashid. Amit Mishra has also been a gun performer in the playoffs with an Avg of just 14 and economy under run a ball. Tahir has been highlighted for his impeccable average of 17.
Fun Fact: Rashid Khan also has the best ever Batting SR in powerplays for a minimum of 10 balls faced.
Too early to call him a Legend?

There is only one category (least Economical Venues) spared by Rashid where he wasn't mind-blowing. Otherwise, he topped 6/10 parameters discussed above giving a deja-vu of ABD's performance in the analysis of Top 10 IPL batsmen.

Suffice to say that there is no better bowler than the wristy magician in IPL history, so far.