I selected 3% but that would be an unusual loan, sound trustworthy platform, secured against an occupied or ready to be occupied residential building at low LTV. Higher than that all the premium would be to cover risk. If others will not participate at such low rates I wonder what they do with their cash? Opt for safety with FSCS at c1% or go for S&S where the risks are even more difficult to assess. Or simply gamble.
All my posts are my personal opinion and are not advice. History suggests that, if anything, it would be more profitable to do the opposite of whatever I do, but whatever you do will not be any responsibility of mine.
I haven't tried Archover, but the other 6 you mentioned are also running at over 6% XIRR for me.
The following are also running above the 6% level for me:
ABLrate, MoneyThing, Mintos (though no longer open to new loans for UK lenders), Robocash, Grupeer, Find Ourselves (though suffering considerable cash drag here).
Lendy is also technically in this bracket for me, but obviously won't be by the time the dust settles.
The following are also on target to achieve over 6% XIRR, but don't yet qualify, as, like you, I don't include accrued interest in my calculations. This is a little unfair on these platforms as they don't generally pay profits (at least not total profits) until the loans have been repaid:
Brick Owner, CrowdProperty, CapitalRise, British Pearl, Uown.
I'm an equity investor in AxiaFunder and a minor equity investor in Welendus(FO), Brickowner, Crowdstacker, Proplend, ABLrate, CrowdProperty, Assetz Capital, Elfin Market, Qardus & Loanpad. This time next year I'll be a miwionaire Rodders!