what dunlop do you get?

I'd take 150/70, 150/60 is for wider rims, also, the Ninja old 250SE came with 150/70 iirc

yeah, should be.

but, the road5 have dual compound, and on the sides of the rear tyre are super grippy compound like hypersports.
if you lean over, there is a sharp change of feeling that need getting used to. IINM, the new road6 took away this compound.

also, different brand tyre gives different feeling, especially when turning a bike, for a learning rider.
if affects turning at different speeds, slow, medium, and fast. some ppl can adapt, some ppl just pick a brand and use it forever.

check your rim width, is usually stamped on one of the spokes or somewhere on the rim, looks something like MT17x4.00. this is the rim diameter and width, and the width determines what tyre size it can take. my personal opinion, is to use the middle size, or go down one size for less aggressive riders. down size usually gives more surface area at low lean angles, and opposite for up size. but, at the cost of high speed stability.

arrowmax is bias, and road5 is radial. make sure the front you get a matching radial tyre otherwise learning to ride the bike will become strange. stick to original size for the front wheel.

other options are:
Metzeler Roadtec series (Z8, Roadtec01 etc)- usually the cheapest around here, but if you compare overseas price, they are up there
Pirelli Angel series
Bridgestone T series (T30 evo, T31, T32)

Budget conscious and recommended, msotly bias ply:
Corsa Platinum series
Maxxis Volans (dual compound)

and many other sport touring tyres...

hypersport tyres will give the best riding experience, maybe someday when you're ready

do not trust any tyres in the wet, that's all I can say

full silica is best in the wet, but they die faster in the heat, or parked under the sun UV will kill the tyres

the best bet would be Michelin Road series, or Metzeler Roadtec series, or Pirelli Angel GT series
if you want sports bias tyres, Battlax S22 and Metzeler M9RR are the best in wet, Rosso also ok

I have used Metzeler Roadtec01, Michelin Power GP, Metzeler Racetec RR (rear) all in wet and dry - rear tyre will almost always lose grip no matter what

Kapcai I trust Corsa platinum series and Bridgestone battlax BT39 both wet and dry

if you want lower cost options, you can consider non-radial tyres like Corsa Cross but they don't have your size
probably just fit 110/80 and 140/80

when you change new tyres, get used to the new tyre profile first, the tyre will handle differently
also need to change the pressure, and find out which one gives you the best confidence, especially the front tyre

it should go up to 30k kms if pressure and suspension are ok

tyre size... make sure suitable for the rim width
I test different size on rear, +1 width but +/-1 height

example: stock rear 150/70
- 150/60 or 160/60

For 140/70 can try 130/70

in my experience, dropping the sidewall profile on the same width, will actually require a wider rim, example, 140/60 (sidewall 84) vs 140/70 (sidewall 98), the 140/60 actually not suitable for the rim that the 140/70 comes with

going up 1 size, from 140/70 (sidewall 98) to 150/70 (sidewall 105) is actually ok, but really is for people who wants more safety margin when the bike is leaned over, aka more chicken strips

going 140/70 (sidewall 98) to 150/60 (90) means may need a wider rim to use the 150/60, 150/70 (sidewall 105) is more suitable

for rear tyre, tall sidewall is actually better, especially if you want to run lower pressure to keep the tyre heat in