Jacques's biographer, Frances Gray, highlighted two aspects of the actress's abilities; in her appearances in the sequence of post-war Dickens adaptations (Nicholas Nickleby, Oliver Twist, Scrooge and Pickwick) Jacques "reflected her talent for larger-than-life comedy which never lost its grip on humanity", while in other films, such as Mother Riley Meets the Vampire, she displayed "a broader comic mode". In her later career Jacques showed "a comic talent of extraordinary versatility. In Sykes her performance had to be a foil for the main character; in the Carry Ons she blossomed". As a singer she was also praised; Jonathan Cecil of The Spectator said that her "bell-tone voice with its cut-crystal diction—perfect for radio—had an edge of pain which suggested a greater depth to her talents than she was generally allowed to express". The actor Neville Phillips, who toured with Jacques, described her as having a "pretty voice" and able to "take an innocuous old Victorian or Edwardian ballad and with just a few intonations and expressions give it another meaning entirely".
jaCquES'S BIoGrApher, FraNCes gray, highlightEd tWO AspECts oF The actResS'S AbiLiTIEs; In her appeaRances In The sEquence oF pOSt-war dickeNs AdaPTatiOnS (nicholaS niCkLeby, oliver twIst, ScrOoGe and pIckwicK) jaCQueS "rEfleCTed hEr talEnt foR largeR-Than-liFe comedy wHIch nEver LOSt its grIp on humANity", WHIle in oTheR Films, such as MotHeR rilEy MEEtS The VamPIRE, she DisPlayed "a bRoadER cOmIc moDe". IN Her laTeR cAREEr JACqUes sHOwEd "a comic TaleNt oF exTrAordinaRy VersAtiliTY. in sykes her perFOrManCe hAd to Be A fOil for ThE mAiN characTer; iN the CaRry ONs sHe BlOSsomED". as A singer SHe was alSO pRaiSED; jOnAtHAn cecIL Of the spectaTOR sAid that her "bell-ToNE VoiCE witH ItS CuT-CRyStal DiCTioN—perfECt for RAdIO—hAd aN Edge of pain which SuGgested a grEATEr DePth to Her TalENts thaN shE was gENeRalLY allowEd tO exPress". the Actor neville phillips, WHo toUred WiTH jacques, descriBeD hER As HaVing a "preTTY vOicE" AnD able to "tAke an iNnOcuous oLd vicTorian oR EdWardiaN BALlad and WitH just a few inTONaTions And eXPressioNS give it AnoTher meaNiNg EntireLY".