Hobbywing Max10 G2 sensored (140A with a 3665 motor)
Hobbywing XR10 Pro with your choice of motor
Hobbywing XR8 with Hobbywing 550 motor
Tekin RX8 with Tekin 550 motor
3000 - 4600kv range ? (questionable)
Will you be running normal 2s for a 1/10 indoor track, or 4s (mainly meant for 8th scale) on an outdoor track?
If 2s, the Max10 and XR10 options will be best. For 4s an 8th scale esc with a lower kv motor will be best. The Max10 G2 can also run on 4s if its the 140A esc with the 2400kv motor only, but just watch temps.
I run a Max10 G1 SCT 120A sensorless with a 550 4000kv motor in my slash 2wd. I raced it a couple times and it was alright. It was sensorless tho.
Back in the day when my uncle was into RC, in his 4x4 SCT (Losi SCTE and TLR SCTE 2.0) he ran a Hobbywing V2.1 mainly, and he ran a XR10 Pro for a little bit, with a 550 4.5 Novak motor. It was a beast, but now those motors are rare, found a few on eBay going for around 150 bucks +, insane.
I was also thinking about getting a Slash 4x4 Ultimate, or the new BL2s but roller off of eBay, and start a little cheaper project, slash 4x4 but for racing, I like my 2wd, but 4x4 will be better for me (more controllable in the air, more grip in the turns, and the local track only runs 4wd)
Slash 4x4 chassis is a bit compact. So not sure if a full 8th scale esc and 550 motor would likely to fit in there compared to what is normally in there RTR from the factory. (Not as spaced out and open as a SCTE or SCT410)
What surface you gonna be running on?
Outdoor dirt = softer compound mini pin like tire
Indoor hard packed / sealed dirt "clay" = bar tire or slick with traction compound
Indoor carpet= harder compound mini pin or wedge tire
Turf= Same for carpet, or bigger lug / knob tires
On my 2wd, I run DE racing wheels, I like the Trinidad ones, like the design.
I run Schumacher Mini Pins front and rear for indoor carpet (mix of black crc and grey eos) I might try Fuzz bite / Swagger or Pin Down / Swagger in the future.
I run JConcepts Smoothie Greens front and rear for indoor sealed dirt "clay" with traction compound. I been using FDJ Yellow dot and its been pretty good.
But tires are different from car to car and track to track, so I would talk to the locals and see what they run.
Edit: 10th scale esc and 540 motor can also work if space is an issue
I have seen countless drivers show up with a Slash at the clubs in my area and very rarely do we see a Slash make it through a full race day without 1 or more broken parts. Yes there are some key upgrades that will help, but unfortunately most upgrades will also fail due to the dated geometry. Typically by the 3rd or 4th race day, the majority of drivers will come to the realization that they need a true race grade platform.
Don't get me wrong, TEKNO will break too, but not nearly as quickly as the Slash. In the long run, you'll save a lot more money and spend far less time making repairs with a TEKNO.
For the record, I have no affiliation with TEKNO, just trying to help you out