Is it likely 1 will still be around at 21 with the Houston pick?
There is a huge group players projected to go around 18-25.
2nd tier WRs
2nd tier OTs (Mims, Fuaga, Barton, Fautunu)
2nd tier DLs (Verse, Chop Robinson, Trice)
Most of the 1st tier CBs (Lassiter, Wiggins, McKinstry, Dejean, Arnold)
At WR either Keon or Brian Thomas should be available.
If the isn't a WR, then that only means that better players at other positions will be available.
Of course this is VERY premature. The high level "locked" draft ranking are not completed until mid April.