Oil surge management sounds reassuring :)
Yeh I don't think Iain or Adrian run extra sump setup and they do low 1:13s. Even with said handling mods I don't think the car is even capable of said times lol but I still think it's cheap insurance for those with extra pocket money hehe. I'm thinking sometime in the near future (MTC :P) but only once I get my Koni's
At least it's a functional mod instead of a body kit hahahah jksssss (to each their own)

Yo Tree. I wouldn't bother with an accumulator or any of that. The only time you'd need that was if you had a kick ass suspension setup, aero and full slicks. If you really wanted to do something a baffled sump should be more than good enough. If you wanted to check first, get an oil pressure gauge and if you if you start sucking in air, the pressure should drop (I think... just guessing).

Nek minute engine blows LOL jks
The problem with oil press gauge is that by the time you see the needle drop it's already too late. But still useful for choose optimal oil weight.
Also if we overfill the oil wouldn't that put stress on the crank thus robbing power and cause some frothing?

An extra 100mml of oil will basicaly sit in the sump,
Get a pressure gauge to see if the pressure is too much with extra oil

But with all that added weight of electric oil pump etc
I don't see your times changing,
I doubt you or anyone will be cornering hard enough to suck enough air in to blow an engine
Sure go nuts if you want
But at the end of the day it's a 6000$ car that sees a few track days a year.

Put your money somewhere else, like camber adjustable tops
Or a larger front sway bar or a new set of rubber
Because come the next year you will most likely need them :p or a sandwich plate oil cooler to keep temps down a bit

Each to there own in the end

Also isn't that what an oil catch can is for?

Sorry but my car is worth more than 6k LOL 10k at least mang
I'm also adding an A/C I think my car will be 1230 kg by the end of this lol but whatever that's a small increase from 1174 and this is not a race car; even with the added weight driver skill should compensate ;)
I can get 3 deg neg camber at least and prob more with my crash bolts. Don't need front sway bar as it understeers with semis. Good point with the pressure gauge check or too much oil tho

The oil level wont affect pressure, unless its got none. Most cars can hold more oil than what the dipstick says without any drama. When I rebuilt mine I cheeked it out and it was something like 10-15mm over the full line. In the HQ we run 1" over.
Oil catch can has nothing to do with it, its for catching blow by

I guess it really depends on what you class as acceptable oil pressure whilst on the track as to what you need for your car. Also when you are tracking your car your oil temps are a hell of a lot higher than normal, so not only does the oil move around in the pan a lot easier, but your engine is a lot slower to rebuild oil pressure. it is actually quite scary when you begin to log oil pressure at the track. Here is an example have handy:

This is an evo with stock baffling in the sump, hard compound semis with no aero, and this is a 1:36 lap around winton. It was .5l overfilled, which only ended up in the catch can. The blue line can show you where i'm referring to, and you can see by the map down the bottom right where he is at winton.
Now this engine has not been damaged from that one incident, but think how long the engine will last in the long run after a year of track days, if he gets more time in the car and gets quicker, softer tyres etc. That was logged from the main oil gallery where the factory sensor sits.

In terms of insurance value
Your car wouldn't be much more then. 7.5k

Whether you can get 10k is a different story.

But
I would put money into oil cooling and a catch can.

Also in terms of a sway bar
One reason a car hndersteers is that your tyres are not on the ground properly so it under steers
And bigger away bar up front will help stick your tyres to the road harder rather then let them come unstuck in hard cornering
Many people have confirmed a lot better traction and less hndersteers with a larger front bar

White line do a good. 3 way adjustable one

Each to there own however :)
Good luck with the baffling be interesting to see how it goes.

Just a FYI Tree, group N 3sge beams Celica's that raced in a one make series in Japan used stock sumps.