update 5/27/2019: it's a mess but i'll clean this page up later.
-- so i tried a few props today, 3025, hq3x3x2, avan 3"
-- betaflight4 gives you propwash more than BF3 and older. i find that props 3025, hq3x3x2, avan 3" give you the least propwash. but they are slower than gf3028, hq3x3x3. they are slower and draw less amps but that makes sense right ? power comes from somewhere and it happens to be the batteries :)
-- 3025 props and hq3x3x2 are about the same in speed and flying charateristic. they draw less amps so you can use smaller batteries and that helps propwash even more.
-- avan 3" are in the middle of bi blades and tri blades. they are tri blades and very light. speed is about the same as bi blades. they have the most control at low throttle out of all other props. and draw less amps, so you can use small batteries and that also helps with propwash.
-- gf3028 and hq3x3x3: if you just do wide turns and power loops and don't mind propwash. they are the fastest and that means more amp draw. the speeds between the two are the same. gf3028 are lighter and lower pitch so they spin up faster than hq3x3x3. and i like them with bigger batteries which are not helping with propwash.

-- i'm lazy so i just tried those props with the same pid.
-- so you just try those props out and see which one you like the most and use them.

-- about tuning: my pid is not great. you just move P up and down a bit to see if it flies better.
-- removing some of filters in BF4 would help with propwash but be careful. always check motors temperature.
-- BF3.x.x can tune out most of the propwash but the motors will get hot. BF4.x.x with dynamic D gain help with hot motors but gives propwash.

update 5/18/2019:
-- so i made another one. this one with 1105 7500kv instead of 1105 6000kv. it's a few grams heavier ( because these gemfan 1105 7500kv motors are heavy ) so not happy about that, but they are still good motors, they're just heavy.
-- it flies really great. 68g dry, gemfan 1105 7500kv, gf3028, 3s 550mah or 3s 650mah.
-- this is 1105 spinning 3" props, so weight is very restricted, don't make it heavier or you might burn your motors.
-- and check your motors' temperature.
-- i leave betaflight setting at the bottom. it should be ok with 1105 6000kv motors.

even when cruising around at 35-40% throttle, it's already fast. ( of course, for 1105 motors )
it makes my flying corner feel small.
you can get 5-6mins easy or 7mins if you're just cruising.
i like this build with hq3x3x3 more than gf2540
the videos look bad. that's because i'm using an old 40$ box goggles that nobody uses anymore.
i'm sure it'll look a lot better with your 700$ fatshark goggles

i have another build, kind of relate to this one. same build, but different motors and props.
basically, you just swap out motors and props.
63g 12a ( and up) esc 1402 gf2540 3s 550mah.
what you'll get ? a little bit slower than this one. but the control, throttle resolution, is much better.

61g dry, 98g with 3s 350mah, 3-4min ( 3s 450mah if you want more weight ) with gf2540
3s 550mah 650mah with hq3x3x3
betafpv 15a fc+esc, or geprc 12a, or betafpv 12a, or iflight 12a whoop board.
hglrc flame 1105 6000kv or 7500kv (faster)
tbs pro32 nano vtx, modula7 camera(chopped off vtx)
tweaky 120mm whoop frame, built for Line of Sight, very light, minimalist ( to get the frame, you just post messages on rcgroups, that's how they like to operate)

pid: is flyable, need more tuning.
props: gf2540 or hq3x3x3
R : 41 45 25
P: 45 50 27
Y: 40 100
tpa 2.5 breakpoint 1590

stupid eos2 camera looks so bad. we need a new eos2. small capacitor is needed if you want smooth video.
punchouts is usually about 50%. i usually don't fly fast.

4/8/19 update: i chopped vtx from modula7 camera and modified cam mount to fit. i can see a lot better now. it might be just mine. eos2 cam is the worst. i'll upload a video tomorrow.
4/9/19 update: the pictures show modula7 cam with vtx chopped off.
4/11/19 update: i tried hq3x3x3 3s 550mah. it feels good. using same pid as gf2540.
4/11/19 update: it was very windy. frame shake a lot. but i feel i need to record a dvr footage with these hq3x3x3 3s 650mah to show how it flies. i'll make another video on a better day. it flies really good for 6mins.

4/14/19 update: my old goggles can only record 3min at a time. it stops at 3min and starts again.

5/29/2019:
my thought on avan 3" props. avan 3" are lighter, so i can use smaller batteries, 3s 550mah. it's still slower than gf3028 3s 650mah.
geprc 12a 3s 1105 6000kv. i like 3s 1105 7500kv more.

5/18/2019: pid for 1105 7500kv but should be ok with 1105 6000kv. pid is not good, but it's fliable.
-- i copy and past from BF presets and made some changes. (https://github.com/betaflight/betaflight/wiki/Community-Presets)
betaflight 4.0.2

Filter Settings

set gyro_lowpass_type = BiQUAD
set dyn_notch_min_hz = 150
set dyn_lpf_gyro_min_hz = 150
set dyn_lpf_gyro_max_hz = 700
set dyn_lpf_dterm_min_hz = 150
set dyn_lpf_dterm_max_hz = 250
set dterm_lowpass_type = BiQUAD
set dterm_lowpass2_hz = 150

PID Gains Settings

set anti_gravity_gain = 5000
set p_pitch = 50
set i_pitch = 95
set d_pitch = 30
set p_roll = 46
set i_roll = 88
set d_roll = 27
set d_min_pitch = 18
set d_min_roll = 16
set d_min_boost_gain = 30
set d_min_advance = 0

Assumes Freestyle | For racing use "Setpoint" and cutoff = 20

set iterm_relax_type = GYRO
set iterm_relax_cutoff = 11

TPA Settings (which is D-term only by default)

set tpa_rate = 40
set tpa_breakpoint = 1600