No clue, but I'll guess. (TLDR my guess still top 25)
BTW the ESPN advanced metrics/efficiency ratings had the Texas defense at #5 last year and the offense at #97. Right near where the other system, FEI, had it.
Well, the D keeps Orlando and his system which year two should be a marginal improvement alone with second year in a new system for both the players and coaches. However, they lose Poona, Malik, Hill, and Elliot who were arguably the best players at each level of the defense.
It's hard to expect no drop off, but they should still be solid to very good. A good indication would the bowl game vs Mizzou, one the of country's best offenses and one of the top QB's who may be the first guy off the NFL board next draft. That game was played without Malik, Hill, and Elliot on for the draft, plus Chris Nelson was out due to injury. Only Poona played in that game and the D still absolutely dominated arguably the SEC's top offense (Big 12 just too physical
Texas held Mizzou to 20 points below their season average, over 100 yards of offense below their season average, and allowed only 5 yards per play down from their season avr. of 7.2
So, without the guys leaving and Chris Nelson out it was still a great D. But....there won't be the best punter in football this year pinning back the opposition deep all day, AND there is no way the D will be as lucky on the injury front. The D last year had a relatively very healthy year (whereas the offense was extremely unusually harsh).and it's unlikely they will be as lucky this year.
With all that, I would guess they should still be a top 25 defense with a decent shot at holding serve and being a top 10 D. Even if they are a top 25 D they just need the offense to get out of the gutter (which will help the D) and there should be some more overall improvement into Herman's second year.