I need to use the STIX math italic (second row) and math bold italic (third row) in the same text. I found that the distinction for all small greek letters except lambda is visible enough. The shape of lambda seems to be inconsistent (too thin). Since I have both typefaces in the same text, the two lambdas can hardly be distinguished. What could be the solution in this case?

Currently, I am defining the serif-less bold italic small greek math letters

\DeclareMathSymbol{\alphaSF}{\mathalpha}{arrows2}{"0B} \DeclareMathSymbol{\lambdaSF}{\mathalpha}{arrows2}{"15} \newcommand{\lambdaBold}{{\bm{\lambdaSF}}} \newcommand{\alphaBold}{{\bm \alphaSF}} 

and using them instead of bold italic, but serif-less fonts stand out too much.