The rates on ehealthinsurance or any other online quoting system are always going to be the best possible rate (or preferred). From what I have been told by the sales reps that I work with at the insurance companies, approx. 60% of the population will qualify for preferred rating. Whether you take medications or not, if you have an ongoing health condition, there will likely be one of three possible outcomes: a decline, an exclusion Rider or an increased rate factor. (It all depends on what kind of risk your current condition presents to the insurance carrier. For example, if you have a condition that will likely result in a surgery sometime down the road, a decline is very likely.)
In Colorado, Humana One rates up in factors of 10% increments. BCBS, Aetna, Time Insurance and Golden Rule typically rate up in factors of 25% increments. Golden rule is more likely to exclude something from coverage rather than rate up. Rocky Mountain Health plans is going to either exclude or decline rather than rate. Underwriting guidelines vary greatly from one insurance carrier to the next. For example, one carrier might decline you for Morton's Neuroma, while another one would accept you if it has been surgically corrected with a complete recovery noted in your medical records. Your best bet is to contact a broker for a prescreen if you have pre-existing conditions so you don't waste your time.
Sore throats and ER visits for acute illnesses are not going to present a problem with underwriting. It's only the ongoing conditions that really cause you to get rated or have exclusions of coverage.