Handheld optical coherence tomography (HH-OCT) systems enable point-of-care ophthalmic imaging in bedridden, uncooperative, and pediatric patients. Handheld spectrally encoded coherence tomography and reflectometry (HH-SECTR) combines OCT and spectrally encoded reflectometry (SER) to address critical clinical challenges in HH-OCT imaging with real-time en face retinal aiming for OCT volume alignment and volumetric correction of motion artifacts that occur during HH-OCT imaging. We aim to enable robust clinical translation of HH-SECTR and improve clinical ergonomics during point-of-care OCT imaging for ophthalmic diagnostics. HH-SECTR is redesigned with (1)optimized SER optical imaging for en face retinal aiming and retinal tracking for motion correction, (2)a modular aluminum form factor for sustained alignment and probe stability for longitudinal clinical studies, and (3)one-handed photographer-ergonomic motorized focus adjustment. We demonstrate an HH-SECTR imaging probe with micron-scale optical-optomechanical stability and use it for in vivo human retinal imaging and volumetric motion correction. This research will benefit the clinical translation of HH-SECTR for point-of-care ophthalmic diagnostics.