You'll get your head spinning like an LP on a turntable if you keep this up
Kidding aside, it's unlikely there is a "right" decision to be made. As you can see from the posts there are a lot of favorite carts from different folks and they aren't all the same or for the same reasons. Going from your description of forward and bright/detailed I think some carts with a ML stylus would be in that neighborhood. Audio Technica can have that kind of sound in a lot of systems/environments.
I have a RB300 arm on one of my tables. Not the same level as the RB900, but I think the mechanics and cart matching are similar. Among others I have had a Denon DL-160 (up line from similar DL-110, but NLA) and Audio Technica AT155LC(with ATN150Sa stylus) on that arm. I sold the Denon with relatively low hours on it, I sold it because it did not stand above the Audio Technica. Overall it was not as versatile. The AT has multiple replacement styli and at best I thought the Denon somewhat redundant.
The point is that the AT cart worked well for me with the arm mentioned. The Denon was a fine sounding cartridge and I would have been happy to have it still if I was without the AT
Now a little something on AT carts:
AT has cartridge "Groups" . These groups are designed to accept styli that have compatible "grips", the plastic part that acts as the carrier that attaches the stylus/cantilever to the cartridge body. Previously in this thread some AT carts were mentioned. The VM95 series is a different group than the one the VM540ML comes from. They may each offer styli with similar profiles, but the grips won't fit outside their group.
The VM540
ML is part of Group K and comes with a ML (Micro Line or Micro Linear stylus). Other current Group K offerings are (C)Conical, (EB)Bonded Elliptical, (EN)Nude Elliptical, (SH)Shibata, and (SLC)Special Line Contact. My AT155LC from 1981, is also Group K and has an earlier generation of LC (Line Contact) stylus. I can buy a brand new VMN40ML stylus that fits today's VM Group K series carts and drop it in my 42 year old AT155LC. The group K has been AT's top tier moving magnet cartridge since the late 1970s and have been supported throughout. Choices through the years have had many different diamonds and cantilever materials. The current top group K cart is the VM
760SLC at around $649. The VM
540ML($279) is in the same line-up and would carry similar internal parts with a lesser cantilever, diamond and body structure. The VM
740ML($349) has the same stylus as the VM
540ML, but has a metal body as opposed to the VM540ML's resin body. VM
760SLC and VM
740ML and VM750SH have the same metal body with each having a different stylus.
Additionally there appears to be available from a couple of vendors (
HiFi Heaven at least) the AT 440MLb,
the predecessor to the $279 VM540ML. There are a couple differences, but I would estimate them to be small. The AT 440MLb can be had for $60 less at $219. Still Group K. This has a lower recommended tracking force and although not spec'd as such might have a slightly higher compliance. The HiFi Heaven description says gold plated beryllium cantilever, but it is not.
Audio Technica Group K has had a long line of cartridges and styli for over 40 years. The AT 440MLb
seems to me like the budgetary bargain in that group at the moment.
I don't know where you get a new AT VM740ML for $244. That would be a very good price. I see there is also a VM540ML at another site for $249....this would indicate (to me) that they are not an authorized AT seller as AT seems pretty strict about their pricing from approved vendors.