It's definitely time for a new sensor. The 20MP sensor is good, but there are a number of areas where tech has moved forward and it could stand an update. I'm not looking for world-beating updates but rather just the last 4 years of evolution applied to the 20MP sensor to get those iterative updates. Same thing for the processor, TruePic IX seems either underpowered or underutilized.
Sensor readout speed is one major area. While the 20MP sensor remains probably the third best sensor on the market for this, larger sensors are getting very close and since size directly benefits readout, an updated sensor could improve things here. A stacked sensor would be even better. Note that faster readout directly benefits non-sports shooters as well, it allows for higher EVF refresh, faster multi-shot capabilities and even the possibility of silent shutter with flash sync (like the A1 introduced thanks to it's 1/200 readout). I'd like to see some more PDAF sensors, but not at the cost of cross-type sensors (which remains a unique Olympus offering for some insane reason, I was expecting cross-type on the A1 and consider the lack a major miss for Sony)
Another area is the EVF. The current EVF in the E-M1's is adequate at best. It was excellent when introduced on the E-M1, very good on the E-M1.2 and E-M5.2, quite disappointing on the E-M1X and verging on laughable on the E-M1.3 in a market where a 3.68MP 0.8x EVF is actually getting complaints about being somewhat out of date on a $2k USD body (Z6II), note Fuji and Panasonic both offer significantly better EVF's in their bodies which compete with the E-M1.3, as does Nikon's Z5. I expect the limiting factor here is the processor, especially for the E-M1X. An E-M1X.2 should have a truly competitive EVF, which means at least 5.44MP at 0.8x for its pricepoint, and maybe even Sony's 9.44MP unit.
Battery life is another area, I'd like to see an update of the BLH-1 chemistry to get more capacity from the same package. We've seen a number of other makers do this, most recently Nikon with their EN-EL15c. The BLH-1 was the biggest capacity battery in Mirrorless when introduced, it's now pretty much the lowest capacity of the 'big' batteries. Another option that should be explored with an updated E-M1X would be providing a single high-capacity battery option (like Nikon's EN-EL18), that could potentially make an HLD-10 for the E-M1.2/3 viable as an HLD-9 replacement.
I'd like to see more evolution in the multi-shot capabilities. LiveND in particular needs to evolve (OM Digital should go use Sony's sadly-abandoned Smooth Reflections app for ideas, it's still best in class for simulating ND filters). Computational Photography is an area where Olympus leads and they absolutely need to keep pushing here. I'd love to see the ability to combine features here, like high-res and focus stacking or high-res and HDR. In-camera Brenizer stitches would be a great capability to add.
Everybody sucks at mobile device integration. This is a real area that needs improvement and can benefit the full line. I'd like to see the ability to get high-speed wireless connectivity between the camera and phone/tablet (Sony has finally taken a step in that direction with the A1 and Xperia Pro) plus I'd like to see an app that allows you to fully control the camera (including settings) and let you configure & trade JPEG image settings easily (maybe go license some brands from Kodak to do Fuji-style film simulations based on Kodachrome/Tri-X/Portra/etc). Nikon did half of this (easily swap settings files) and Fuji the other half (great JPEG settings with the right configuration options) but somebody needs to do both.
Sensor readout speed is one major area. While the 20MP sensor remains probably the third best sensor on the market for this, larger sensors are getting very close and since size directly benefits readout, an updated sensor could improve things here. A stacked sensor would be even better. Note that faster readout directly benefits non-sports shooters as well, it allows for higher EVF refresh, faster multi-shot capabilities and even the possibility of silent shutter with flash sync (like the A1 introduced thanks to it's 1/200 readout). I'd like to see some more PDAF sensors, but not at the cost of cross-type sensors (which remains a unique Olympus offering for some insane reason, I was expecting cross-type on the A1 and consider the lack a major miss for Sony)
Another area is the EVF. The current EVF in the E-M1's is adequate at best. It was excellent when introduced on the E-M1, very good on the E-M1.2 and E-M5.2, quite disappointing on the E-M1X and verging on laughable on the E-M1.3 in a market where a 3.68MP 0.8x EVF is actually getting complaints about being somewhat out of date on a $2k USD body (Z6II), note Fuji and Panasonic both offer significantly better EVF's in their bodies which compete with the E-M1.3, as does Nikon's Z5. I expect the limiting factor here is the processor, especially for the E-M1X. An E-M1X.2 should have a truly competitive EVF, which means at least 5.44MP at 0.8x for its pricepoint, and maybe even Sony's 9.44MP unit.
Battery life is another area, I'd like to see an update of the BLH-1 chemistry to get more capacity from the same package. We've seen a number of other makers do this, most recently Nikon with their EN-EL15c. The BLH-1 was the biggest capacity battery in Mirrorless when introduced, it's now pretty much the lowest capacity of the 'big' batteries. Another option that should be explored with an updated E-M1X would be providing a single high-capacity battery option (like Nikon's EN-EL18), that could potentially make an HLD-10 for the E-M1.2/3 viable as an HLD-9 replacement.
I'd like to see more evolution in the multi-shot capabilities. LiveND in particular needs to evolve (OM Digital should go use Sony's sadly-abandoned Smooth Reflections app for ideas, it's still best in class for simulating ND filters). Computational Photography is an area where Olympus leads and they absolutely need to keep pushing here. I'd love to see the ability to combine features here, like high-res and focus stacking or high-res and HDR. In-camera Brenizer stitches would be a great capability to add.
Everybody sucks at mobile device integration. This is a real area that needs improvement and can benefit the full line. I'd like to see the ability to get high-speed wireless connectivity between the camera and phone/tablet (Sony has finally taken a step in that direction with the A1 and Xperia Pro) plus I'd like to see an app that allows you to fully control the camera (including settings) and let you configure & trade JPEG image settings easily (maybe go license some brands from Kodak to do Fuji-style film simulations based on Kodachrome/Tri-X/Portra/etc). Nikon did half of this (easily swap settings files) and Fuji the other half (great JPEG settings with the right configuration options) but somebody needs to do both.
Some people like the sound.
. 
along with a list of other nitpicks.
