Most will not be competitive. SD-6, HD-117 and
maybe HD-119 could be interesting.
HD-4 is a very safe Republican seat covering Dalton. Safe R, may be an RvR runoff, although there is a Democrat in the race.
HD-26 is a very safe Republican seat in Forsyth County. Safe R, may be an RvR runoff, although there is a Democrat in the race.
HD-42, covering parts of Smyrna and Dobbins Air Reserve Base in Cobb County, seems on its face like a relatively marginal Democratic seat (though don't have voting figures), but no Republican filed. Teri Anulewicz (D) is the only candidate, so she will be acclaimed.
HD-60 is a very safe Democratic seat in south Fulton and north Clayton Counties, and in any case no Republican filed. Three Democrats will compete for the seat. Safe D.
HD-89 is a very safe Democratic seat in southwest Dekalb County, and in any case no Republican filed. Four Democrats will compete for the seat. Safe D.
HD-117 is a lean Republican seat covering what might be called exurbs of Athens in Barrow and Jackson Counties, suburbs of Athens in Oconee County and part of Athens proper (which is cracked across three districts). Moved hard towards the Democrats in 2016. Will be decided in the jungle as there are only two candidates (one Democrat and one Republican). Lean R.
HD-119 is a likely Republican seat that takes some of the more marginal parts of Athens and attaches them to rural Oconee County (the most suburban parts of Oconee, which are also moving sharply towards the Democrats, are in HD-117). Plausibly could be competitive in this environment but probably will not be. Likely R, Democrat should make it to the runoff as there are three Republicans and only one Democrat.
SD-6 is a marginal Republican-held seat that includes the territory of HD-42 above (perhaps explaining why only one candidate filed there) plus the rest of Smyrna, bits of Cobb County connecting it to Fulton County, north Atlanta and Sandy Springs. It could very plausibly vote for a Democrat and is easily the most competitive seat, although it is unclear to me how serious any of the Democratic candidates are. I would call it a Toss-up.
SD-39 is a safe Democratic seat covering much of Atlanta. A Republican did manage to file, but the runoff, if there is one, will very likely be DvD. Safe D.