"thorny aspect" is correct and can be used in written English.
You can use it to refer to a difficult problem or challenge. For example: "The thorny aspect of this project is the tight deadline imposed on us."
Ms. Linney, an actress of unusual economy and seemingly innate grace, does not shy from depicting the thorny aspects of Sarah's personality: her impatience with views opposing her own, the leftover anger from witnessing her parents' unhappy marriage, the emotional reserve and the sense of detachment bred in her by her work.
George Perle could seem a model of compositional sobriety: a composer of complex but poetic works, influenced by serialism but not wedded to its techniques or accents, and a theorist who wrote with clarity and passion about thorny aspects of contemporary style.
Welles directed another dozen features, but each of them had its difficult, thorny aspects, either in terms of financing, distribution or control of final cut.
The music was the thorniest aspect.
So I thought we could just start with what many people find the thorniest aspect of feedback, which is critical feedback.
Central among the thorniest aspects of implementing the Convention on Biological Diversity (CBD) is how to make progress on the Convention's objectives of guaranteeing appropriate access to genetic sources and arranging for the equitable sharing of benefits derived from these sources.
The concerns for Australia revolve around the thornier aspects of doing business with China.
On Thursday, Vargas launched a crowdfunding campaign for #EmergingUS, a video-heavy digital media outlet he believes can fill a void in covering thorny, overlapping aspects of American identity. .
We noted, for instance, the difficulty of the regulatory issues presented, stating that the "order under consideration is part of the general regulatory system devised for the conservation of oil and gas in Texas, an aspect of 'as thorny a problem as has challenged the ingenuity and wisdom of legislatures.' " 319 U. S., at 318 (quoting Rowan, supra, at 579).
Harvard will also draw on faculty members from outside science to address the thorny ethical, business, and policy aspects of the controversial research.
