Liquidity Aggregation for Small-Mid Sized Prop Firms?

Been looking into setting up a small prop firm, maybe 10-15 active traders initially, focusing primarily on $EURUSD and $XAUUSD. We're running a custom MT5 setup. My main concern is finding a robust liquidity solution that isn't geared solely towards institutional flow. The usual suspects seem to have high minimums or require proprietary tech integration that's a beast to manage. Anyone have experience with smaller, but reliable, liquidity providers or aggregators that can handle decent volume without excessive spreads, especially during volatile periods? Thinking about the trade-off between prime brokerage setup and a more plug-and-play solution. What kind of due diligence should I be prioritizing for these providers beyond just their quoted spreads?