EHP/s is irrelevant. You need HP/s not EHP/s. Big difference. The requirements vary from player to player and from ship / fit to ship / fit, how much speed tank you have, your sig size, etc. etc. so I will tell you how it scales for me, and is mostly applicable to most ships. A note here, shield ships are bit less demending then armor ships because of the passive shield regen, even if you are not fit for shield regen it still adds a little bit to your active shield rep to help you achieve the HP/s, whereas armor ships can not so they need a bit more.
EHP/s is less relevant cause it varies and goes up / down with resistances and can give you a completely false representation of what you need, so look at HP/s, not EHP/s. EHP/s can go up while rising the nymebrs up of off irrelevant for the situation resistance, while HP/s will stay flat.
So here goes, for me, 1st off a Large Faction cap battery is a must. Either on armor or shield. I like it a ton better then having to fiddle around with cap boosters, double this in upper tiers when I have to overheat the booster. It needs to be faction because of the bigger resistance and lower fitting reqs, the T2 or T1 just doesn’t cut it.
Once I have my cap down, both resistance and volume / recharge, then come the reps. For shield ships, to comfortably handle a T3 neut spawn I need to have 90+ HP/s (87, 89 is still ok) this can be relatively easily achieved. For armor fits, this needs to go a bit higher, around 100 HP/s, all while remainign perfectly stable with everything running. In T4s this goes up to around 130 ish HP/s on shield ships, 140ish on armor ships, in T5s I need 150+.
How you achieve those numbers is entirely up to you, you can use your fit (rigs, blinged reps, etc.) boosters, implants, whatever works. Plug it into Pyfa and see. Also, I’d rather have a recharger then a booster, thats just me though, if I were doing that. Switch some of your drones out for thermal (Gallente) drones. They do more raw DPS, but keep the caldari drones as default. You will be taking out battleships a lot faster with Ogres then Wasps.
You can kite the Vedmaks DPS, just go out to like 22-24 km + range, I forgot the exact number, may need to overheat your prop to do so. This may be hard to do while being neuted from the Leshaks, but it is doable, you don’t have to kill all of them, just enough for your tank to stop going down.
You may even consider a 2nd cap battery, medium or small to stack resistances, yeas there is a penalty but you still get a ton of it, and if you lack PG / CPU then dump the Howitzers, focus on being a drone boat. On a 2 armor rep set up, maybe try an anciliary for your 2nd rep, it will give you an “oh fck” button, you will use a single rep as default that one being as cap efficient as it can possibly get, while the anciliary will become your big one, burst rep.